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stem
stem supporting structure of a plant, serving also to conduct and to store food materials. The stems of herbaceous and of woody plants differ: those of herbaceous plants are usually green and pliant and are covered by a thin epidermis instead of by the bark of woody plants. There is relatively more pith in herbaceous stems, and the cambium , which increases the diameter of woody stems, is usually almost inactive; it is therefore characteristic of herbaceous stems that, although they increase in height, their increase in diameter is small. Most herbaceous plants are annuals; some have specialized underground stems (see bulb , corm , rhizome , and tuber ) that store food and enable the plant to survive unfavorable growing conditions. Aerial stems may be specialized as tendrils, thorns, or runners (stolons); another specialization is the fleshy, moisture-retaining stem of many arid-land plants (such as most cacti and other succulents). Aerial stems are usually erect; however, in the climbing plants they require support and in others (e.g., melons) they are prostrate. The vascular system in the stem consists chiefly of xylem (upward-conducting) and phloem (downward-conducting) tissue, usually in vascular bundles arranged concentrically on either side of the cambium—the xylem ( wood ) inside, the phloem outside. In monocotyledonous plants, which generally lack cambium, the bundles are scattered throughout the stem tissue. The sap ducts are formed of elongated cells joined end to end; in the xylem the cell ends dissolve away completely to form continuous tubes and in the phloem they develop perforations and are called sieve plates. Herbaceous stems are marked externally by leaf and bud nodes; woody stems also bear lenticels (pores for transpiration), scars where leaves, twigs, and fruits have dropped off, and bud scars. The annual extension growth of a woody stem develops from a terminal bud usually protected by bud scales or stipules; when the scales fall away, a characteristic bud scar remains. The sap of certain stems contain gums, latexes, and resins used commercially; many are the source of wood of great economic importance. |
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"stem." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stem." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-stem.html "stem." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-stem.html |
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stem
stem1 / stem/ • n. 1. the main body or stalk of a plant or shrub, typically rising above ground but occasionally subterranean. ∎ the stalk supporting a fruit, flower, or leaf, and attaching it to a larger branch, twig, or stalk. 2. a long and thin supportive or main section of something: the main stem of the wing feathers. ∎ the slender part of a wineglass between the base and the bowl. ∎ the tube of a tobacco pipe. ∎ a rod or cylinder in a mechanism, for example the sliding shaft of a bolt or the winding pin of a watch. ∎ a vertical stroke in a letter or musical note. 3. Gram. the root or main part of a noun, adjective, or other word, to which inflections or formative elements are added. ∎ archaic or poetic/lit. the main line of descent of a family or nation: the Hellenic tribes were derived from the Aryan stem. 4. the main upright timber or metal piece at the bow of a ship, to which the ship's sides are joined. 5. inf. a pipe used for smoking crack or opium. • v. (stemmed , stem·ming ) 1. [intr.] (stem from) originate in or be caused by: many of the universities' problems stem from rapid expansion. 2. [tr.] remove the stems from (fruit or tobacco leaves). 3. [tr.] (of a boat) make headway against (the tide or current). PHRASES: from stem to stern from the front to the back, esp. of a ship: surges of water rocked their boats from stem to stern. ∎ along the entire length of something; throughout: the album is a joy from stem to stern. DERIVATIVES: stem·less adj. stem·like / -ˌlīk/ adj. stem2 • v. (stemmed , stem·ming ) 1. [tr.] stop or restrict (the flow of something): a nurse did her best to stem the bleeding | fig. an attempt to stem the rising tide of unemployment. 2. [intr.] Skiing slide the tail of one ski or both skis outward in order to turn or slow down. |
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"stem." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stem." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O999-stem.html "stem." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-stem.html |
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STEM
STEM, also theme. A term in GRAMMAR and WORD-FORMATION for a ROOT plus the element that fits it into the flow of language. Stems are basic to such inflected languages as Latin and rare in analytic languages like English. In Latin, the root am (love) and a thematic vowel -a- make up the stem ama-, to which appropriate inflections are added: -s in amas thou lovest, -t in amat he/she/it loves. The only stems in present-day English are acquisitions from Latin and Greek. Such stems have no syntactic role, but often decide the spelling and sometimes the pronunciation of derivatives: because negative and auditory derive from Latin negare to deny, audire to listen, their stems are negat- and audit-. Spellings like *negitive and *audatory are therefore not possible. Whereas the rhythm of Latin makes the quality and quantity of all stem vowels clear, the rhythm of English often does not do so, reducing the vowels to a schwa and therefore limiting sound–spelling correspondences. See THEMATIC VOWEL.
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TOM McARTHUR. "STEM." Concise Oxford Companion to the English Language. 1998. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. TOM McARTHUR. "STEM." Concise Oxford Companion to the English Language. 1998. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O29-STEM.html TOM McARTHUR. "STEM." Concise Oxford Companion to the English Language. 1998. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O29-STEM.html |
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stem
stem The part of a plant that usually grows vertically upwards towards the light and supports the leaves, buds, and reproductive structures (see illustration). The leaves develop at the nodes and side or branch stems develop from buds at the nodes. The stems of certain species are modified as bulbs, corms, rhizomes, and tubers. Some species have twining stems; others have horizontal stems, such as runners. Another modification is the cladode. Erect stems may be cylindrical or angular; they may be covered with hairs, prickles, or spines and many exhibit secondary growth and become woody (see growth ring). In addition to its supportive function, the stem contains vascular tissue that conducts food, water, and mineral salts between the roots and leaves. It may also contain chloroplasts and carry out photosynthesis.
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"stem." A Dictionary of Biology. 2004. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stem." A Dictionary of Biology. 2004. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O6-stem.html "stem." A Dictionary of Biology. 2004. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-stem.html |
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stem
stem1 main body of the portion of a tree or other plant above ground OE.; stock of a family XVI; upright stroke, etc. XVII; cylindrical or tubular support XIX. OE. stemn, stefn, corr. to LG., Du. steven :- Gmc. *stamniz, of which a parallel and synon. formation *stamnaz is repr. by (M)LG., (M)Du., OHG. stam (G. stamm), also by OS., ON. stamn, recorded only in the naut. sense (see next); f. *sta- STAND.
Hence stem vb. †rise erect XVI; remove the stalk from XVIII; (orig. U.S.) derive from XX. |
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T. F. HOAD. "stem." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "stem." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O27-stem.html T. F. HOAD. "stem." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-stem.html |
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stem
stem.
1. The foremost timber or steel member forming the bow of a vessel joined at the bottom to the keel either by scarfing, in the case of wood, or riveting or welding in the case of steel. In wooden vessels all the timber strakes are rabbeted to the stem; in steel ships the fore plates are welded or riveted to it. See also cutwater. 2. As a verb, it is a seafaring term indicating that a vessel is holding its own, or making only slight headway, against a contrary tide or current. |
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"stem." The Oxford Companion to Ships and the Sea. 2006. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stem." The Oxford Companion to Ships and the Sea. 2006. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O225-stem.html "stem." The Oxford Companion to Ships and the Sea. 2006. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O225-stem.html |
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stem
stem Main, upward-growing part of a plant that bears leaves, buds and flowers, or other reproductive structures. In vascular plants, the stem contains conducting tissues (xylem and phloem). In flowering plants, this vascular tissue is arranged in a ring (in dicotyledons) or scattered (in monocotyledons). They may be modified into underground structures (rhizomes, tubers, corms, bulbs). Stems vary in shape and size from the thread-like stalks of aquatic plants to tree-trunks.
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"stem." World Encyclopedia. 2005. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stem." World Encyclopedia. 2005. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O142-stem.html "stem." World Encyclopedia. 2005. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-stem.html |
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stem
stem n. the main upright timber or metal piece at the bow of a ship, to which the ship's sides are joined.
v. (of a boat) make headway against (the tide or current). from stem to stern from the front to the back, especially of a ship: surges of water rocked their boats from stem to stern. |
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"stem." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stem." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O63-stem.html "stem." The Oxford Essential Dictionary of the U.S. Military. 2001. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O63-stem.html |
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stem
stem In a vascular plant, the part of the plant that bears buds, leaves, and flowers. It forms the central axis of the plant and often provides mechanical support. Most commonly it is above ground, but it may lie below ground, and is then termed a rhizome.
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MICHAEL ALLABY. "stem." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "stem." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O7-stem.html MICHAEL ALLABY. "stem." A Dictionary of Plant Sciences. 1998. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O7-stem.html |
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stem
stem3 †intr. stop, delay XIII; trans. stop, check, dam up XV. — ON. stemma = (O)HG. stemmen :- Gmc. *stamjan, f. *stam- check (cf. STAMMER).
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Cite this article
T. F. HOAD. "stem." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "stem." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O27-stem2.html T. F. HOAD. "stem." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-stem2.html |
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stem
stem2 †timber at either end of a vessel OE.; upright at the bow of a vessel XVI. OE. stemn, stefn, spec. use of STEM1.
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Cite this article
T. F. HOAD. "stem." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "stem." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O27-stem1.html T. F. HOAD. "stem." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-stem1.html |
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stem
stem4 head in a certain direction XIV; †ram (a vessel) with the stem XV; make headway against XVI. f. STEM2.
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Cite this article
T. F. HOAD. "stem." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "stem." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O27-stem3.html T. F. HOAD. "stem." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-stem3.html |
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stem
stem
•ahem, Belém, Clem, condemn, contemn, crème de la crème, em, gem, hem, Jem, LibDem, phlegm, pro tem, rem, Shem, stem, them
•carpe diem, per diem
•proem • idem • modem • diadem
•mayhem • Bethlehem • ad hominem
•ad valorem • brainstem
•apophthegm (US apothegm)
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"stem." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stem." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O233-stem.html "stem." Oxford Dictionary of Rhymes. 2007. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-stem.html |
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STEM
STEM (stɛm) scanning transmission electron microscope (or microscopy)
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FRAN ALEXANDER , PETER BLAIR , JOHN DAINTITH , ALICE GRANDISON , VALERIE ILLINGWORTH , ELIZABETH MARTIN , ANNE STIBBS , JUDY PEARSALL , and SARA TULLOCH. "STEM." The Oxford Dictionary of Abbreviations. 1998. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. FRAN ALEXANDER , PETER BLAIR , JOHN DAINTITH , ALICE GRANDISON , VALERIE ILLINGWORTH , ELIZABETH MARTIN , ANNE STIBBS , JUDY PEARSALL , and SARA TULLOCH. "STEM." The Oxford Dictionary of Abbreviations. 1998. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O25-STEM.html FRAN ALEXANDER , PETER BLAIR , JOHN DAINTITH , ALICE GRANDISON , VALERIE ILLINGWORTH , ELIZABETH MARTIN , ANNE STIBBS , JUDY PEARSALL , and SARA TULLOCH. "STEM." The Oxford Dictionary of Abbreviations. 1998. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O25-STEM.html |
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