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rod
rod / räd/ • n. 1. a thin straight bar, esp. of wood or metal. ∎ a wand or staff as a symbol of office, authority, or power. ∎ a slender straight stick or shoot growing on or cut from a tree or bush. ∎ a stick used for caning or flogging. ∎ (the rod) the use of such a stick as punishment: if you'd been my daughter, you'd have felt the rod. ∎ vulgar slang a penis. 2. a fishing rod. 3. hist. a linear measure, esp. for land, equal to 51/2 yards (approx. 5.029 m). ∎ (also square rod) a square measure, esp. for land, equal to 160th of an acre or 301/4 square yards (approx. 25.29 sq m). 4. inf. a pistol or revolver. 5. Anat. a light-sensitive cell of one of the two types present in large numbers in the retina of the eye, responsible mainly for monochrome vision in poor light. Compare with cone (sense 3). PHRASES: ride the rods steal rides on freight trains: hundreds of young men took to riding the rods in search of employment. rule someone or something with a rod of iron control or govern someone or something very strictly or harshly.DERIVATIVES: rod·less adj. rod·let / -lət/ n. rod·like / -ˌlīk/ adj. |
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"rod." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "rod." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O999-rod.html "rod." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-rod.html |
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rod
rod In the retina of the vertebrate eye, the more common of the two types of light receptor (compare CONE), which is sensitive to very low levels of stimulation. Many rods (in humans about 150) are connected by bipolar cells to a single ganglion cell whose axon is a nerve fibre in the optic tract; stimuli to the rods are summated (i.e. added together) to produce a total stimulus that must exceed a threshold before an impulse is discharged by the ganglion cell. Because the contribution of many individual rods is summated to produce a single impulse the resulting perceived image is not clearly defined. There are estimated to be about 65 × 106 rods in a single human retina and the eyes of some animals (e.g. opossums) have retinas containing only rods and no cones.
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MICHAEL ALLABY. "rod." A Dictionary of Zoology. 1999. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "rod." A Dictionary of Zoology. 1999. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O8-rod.html MICHAEL ALLABY. "rod." A Dictionary of Zoology. 1999. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-rod.html |
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rod
rod a thin straight bar, especially of wood or metal. In former British usage, a rod was a unit of measurement, the equivalent of a perch.
make a rod for one's own back do something likely to cause difficulties for oneself later. rule with a rod of iron control or govern very strictly or harshly. spare the rod and spoil the child if children are not physically punished when they do wrong their personal development will suffer. It is proverbial, from the early 11th century, and often with biblical allusion to Proverbs 13:24. |
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ELIZABETH KNOWLES. "rod." The Oxford Dictionary of Phrase and Fable. 2006. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. ELIZABETH KNOWLES. "rod." The Oxford Dictionary of Phrase and Fable. 2006. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O214-rod.html ELIZABETH KNOWLES. "rod." The Oxford Dictionary of Phrase and Fable. 2006. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O214-rod.html |
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rod
rod (rod) n. one of the two types of light-sensitive cells in the retina of the eye (compare cone). Rods are necessary for seeing in dim light. They contain the pigment rhodopsin, which is bleached in the light and regenerated in the dark. When all the pigment is bleached (i.e. in bright light) the rods no longer function. See also dark adaptation, light adaptation.
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"rod." A Dictionary of Nursing. 2008. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "rod." A Dictionary of Nursing. 2008. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O62-rod.html "rod." A Dictionary of Nursing. 2008. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-rod.html |
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rod
rod A type of light-sensitive receptor cell present in the retinas of vertebrates. Rods contain the pigment rhodopsin and are essential for vision in dim light. They are not evenly distributed on the retina, being absent in the fovea and occupying all of the retinal margin. See also dark adaptation. Compare cone.
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"rod." A Dictionary of Biology. 2004. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "rod." A Dictionary of Biology. 2004. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O6-rod.html "rod." A Dictionary of Biology. 2004. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-rod.html |
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rod
rod straight slender wand XII; stick for measuring with; measure of length and of area XV. Late OE. rodd, synon. with Continental forms cited S.V. ROOD, but formally distinct; prob. rel. to ON. rudda club.
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T. F. HOAD. "rod." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "rod." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O27-rod.html T. F. HOAD. "rod." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-rod.html |
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Rod
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PATRICK HANKS, KATE HARDCASTLE, and FLAVIA HODGES. "Rod." A Dictionary of First Names. 2006. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. PATRICK HANKS, KATE HARDCASTLE, and FLAVIA HODGES. "Rod." A Dictionary of First Names. 2006. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O41-Rod.html PATRICK HANKS, KATE HARDCASTLE, and FLAVIA HODGES. "Rod." A Dictionary of First Names. 2006. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O41-Rod.html |
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rod
rod see English units of measurement . |
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"rod." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "rod." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1E1-X-rod.html "rod." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-X-rod.html |
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rod
rod •bod, clod, cod, god, hod, mod, nod, od, odd, plod, pod, prod, quad, quod, rod, scrod, shod, sod, squad, tod, Todd, trod, wad
•demigod • amphipod • unipod
•tripod • isopod • myriapod • decapod
•cephalopod • monopod • macropod
•gastropod • arthropod • sauropod
•ramrod • Nimrod • hotrod • pushrod
•goldenrod • Novgorod • slipshod
•roughshod • eisteddfod • tightwad
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"rod." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "rod." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O233-rod.html "rod." Oxford Dictionary of Rhymes. 2007. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-rod.html |
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