stem

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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.

stem

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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.

stem

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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.

STEM

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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.

stem

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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.

stem

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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.

stem

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stem3 †intr. stop, delay XIII; trans. stop, check, dam up XV. — ON. stemma = (O)HG. stemmen :- Gmc. *stamjan, f. *stam- check (cf. STAMMER).

stem

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stem2 †timber at either end of a vessel OE.; upright at the bow of a vessel XVI. OE. stemn, stefn, spec. use of STEM1.

stem

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stem4 head in a certain direction XIV; †ram (a vessel) with the stem XV; make headway against XVI. f. STEM2.

STEM

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STEM (stɛm) scanning transmission electron microscope (or microscopy)