<B>orthotropic, </B>adjective.<DL COMPACT><DD><B> 1. </B>(Botany.) of, having to do with, or exhibiting orthotropism; growing vertically upward or downward, as a stem or root. <DD><B> 2. </B>having to do with or using a type of bridge design in which steel plates, strengthened by longitudinal ribs, serve both as roadway and structural support. <BR> <I>Ex. an orthotropic bridge or girder. The orthotropic deck, a European innovation, was used for the first time in the United States in two bridges completed in 1967 (William H. Quirk).</I> adv. <B>orthotropically.</B> </DL>
<A NAME="orthotropism">
<B>orthotropism, </B>noun.<DL COMPACT><DD> (Botany,) a tendency to grow in a vertical direction, upward or downward. </DL>
<A NAME="orthotropous">
<B>orthotropous, </B>adjective.<DL COMPACT><DD> (Botany.) (of an ovule) having the nucellus straight, or not inverted, so that the chalaza is at the evident base and the micropyle at the opposite end. </DL>
<B>orthoxylene, </B>noun.<DL COMPACT><DD> one of three isomeric forms of xylene. </DL>
<A NAME="ortolan">
<B>ortolan, </B>noun.<DL COMPACT><DD><B> 1. </B>a small bunting of Europe, northern Africa, and western Asia, the meat of which is regarded as a delicacy. <BR> <I>Ex. Let me die eating ortolans to the sound of soft music (Benjamin Disraeli).</I> <DD><B> 2. </B>any one of various small wild birds of North America, such as the bobolink and the sora. </DL>
<A NAME="orts">
<B>orts, </B>noun pl.<DL COMPACT><DD> leftover fragments of food or fodder; scraps; leavings. <BR> <I>Ex. The poor thought the rich were entirely in the right of it to lead a jolly life; besides, their feasting caused a multiplication of orts, which were the heirlooms of the poor (George Eliot). (Figurative.) There, in the shadow of a mountain of yesterday's orts ... in a yard outside the Department of Sanitation's mighty destructor plant, was the car pound (Newsweek).</I> </DL>
<A NAME="orv">
<B>ORV</B> (no periods),<DL COMPACT><DD> off-road vehicle. </DL>
<A NAME="orver">
<B>ORVer, </B>noun.<DL COMPACT><DD> (U.S. Informal.) the owner or driver of an off-road vehicle. </DL>
<A NAME="orwellian">
<B>Orwellian, </B>adjective, noun.<DL COMPACT><DD><I>adj. </I> <B>1. </B>of, having to do with, or in the style of George Orwell (1903-1950). <BR> <I>Ex. The American Dream becomes more dreamlike, and in order to comprehend it one must exercise the difficult Orwellian technique of doublethink (Patrick Skene Catling).</I> <DD><B> 2. </B>characteristic of the regimented and dehumanized society described in Orwell's novel <I>1984.</I> <DD><I>noun </I> a student or follower of Orwell or his ideas. </DL>
<A NAME="orwellism">
<B>Orwellism, </B>noun.<DL COMPACT><DD> the manipulation or distortion of facts for propoganda purposes. </DL>
<A NAME="ory">
<B>-ory,</B><DL COMPACT><DD> (suffix forming adjectives and nouns.) <DD><B> 1. </B>______ing. <BR> <I>Ex. Contradictory = contradicting.</I> <DD><B> 2. </B>of or having to do with ______; of or having to do with ______ion. <BR> <I>Ex. Illusory = of or having to do with illusion.</I> <DD><B> 3. </B>characterized by ______ion. <BR> <I>Ex. Compulsory = characterized by compulsion.</I> <DD><B> 4. </B>serving to ______. <BR> <I>Ex. Preparatory = serving to prepare.</I> <DD><B> 5. </B>tending to ______; inclined to ______. <BR> <I>Ex. Conciliatory = inclined to conciliate.</I> <DD><B> 6. </B>place for ______ing; establishment for ______ing. <BR> <I>Ex. Depository = a place for depositing.</I> <DD><B> 7. </B>other meanings, as in <I>conservatory.</I> </DL>
<A NAME="oryx">
<B>oryx, </B>noun, pl. <B>oryxes</B> or (collectively) <B>oryx.</B><DL COMPACT><DD> an African antelope with long, nearly straight horns in the adult of both sexes. One kind of oryx, the gemsbok, has the longest horns. A rare species of oryx exists in the deserts of Arabia. <BR> <I>Ex. In Arabia Talbot found that the oryx, a handsome black-and-white antelope, is almost extinct (Time).</I> </DL>
<A NAME="os">
<B>os</B> (1), noun, pl. <B>ossa.</B><DL COMPACT><DD> (Latin.) a bone. </DL>
<A NAME="os">
<B>os</B> (2), noun, pl. <B>ora.</B><DL COMPACT><DD> (Latin.) a mouth; opening. </DL>
<A NAME="os">
<B>os</B> (3), noun, pl. <B>osar.</B><DL COMPACT><DD> (Geology.) an esker. </DL>
<A NAME="os">
<B>os-,</B><DL COMPACT><DD> (prefix,) the form of <B>ob-</B> in some cases before <I>c</I> and <I>t,</I> as in <I>oscine, ostensible.</I> </DL>
<A NAME="os">
<B>o.s.</B> or <B>o/s</B> (no periods),<DL COMPACT><DD> out of stock. </DL>
<A NAME="os">
<B>Os</B> (no periods),<DL COMPACT><DD> osmium (chemical element). </DL>
<A NAME="os">
<B>OS</B> (no periods) or <B>O.S.</B><DL COMPACT><DD> Old Saxon. </DL>
<B>O.S.A.</B><DL COMPACT><DD> Order of Saint Augustine; Augustinians (Latin, <I>Ordinis Sancti Augustini</I>). </DL>
<A NAME="osage">
<B>Osage, </B>noun.<DL COMPACT><DD><B> 1. </B>a member of a tribe of American Indians, originally inhabiting the region of the Arkansas River and the Missouri River. <DD><B> 2. </B>their Siouan language. </DL>
<A NAME="osageorange">
<B>Osage orange,</B><DL COMPACT><DD><B> 1. </B>an ornamental, spreading tree of the mulberry family, with glossy leaves and hard, bright-orange wood; yellowwood. It was originally native to Arkansas and surrounding regions. <DD><B> 2. </B>its inedible, greenish fruit that looks somewhat like an orange. </DL>
<A NAME="osar">
<B>osar, </B>noun.<DL COMPACT><DD> plural of <B>os</B> (3). </DL>
<A NAME="osb">
<B>O.S.B.,</B><DL COMPACT><DD> Order of Saint Benedict; Benedictines (Latin, <I>Ordinis Sancti Benedicti</I>). </DL>
<A NAME="oscalcis">
<B>os calcis,</B><DL COMPACT><DD> the bone of the heel; calcaneus. </DL>
<A NAME="oscan">
<B>Oscan, </B>noun.<DL COMPACT><DD><B> 1. </B>one of the ancient inhabitants of Campania, a region in southern Italy. <DD><B> 2. </B>the ancient Italic dialect of Campania, closely related to Umbrian. </DL>
<A NAME="oscar">
<B>Oscar</B> (1) or <B>oscar, </B>noun.<DL COMPACT><DD><B> 1. </B>a golden statuette awarded annually by the Academy of Motion Picture Arts and Sciences for the best performances, production, photography, or other achievement during the year. <DD><B> 2. </B>a prize. </DL>
<A NAME="oscar">
<B>Oscar</B> (2), noun.<DL COMPACT><DD> (U.S.) a code name for the letter <I>o,</I> used in transmitting radio messages. </DL>
<A NAME="oscillate">
<B>oscillate, </B>verb, <B>-lated,</B> <B>-lating.</B><DL COMPACT><DD><I>v.i. </I> <B>1. </B>to swing to and fro like a pendulum; move to and fro between two points. <DD><B> 2. </B>to vary or waver, as between opinions, purposes, or courses of action. <BR> <I>Ex. Human nature oscillates between good and evil (Benjamin Jowett).</I> (SYN) vacillate. <DD><B> 3. </B>(Physics.) <DD><B> a. </B>to have or produce oscillations. <DD><B> b. </B>to swing from one limit to another. <DD><I>v.t. </I> <B>1. </B>to cause to swing to and fro. <DD><B> 2. </B>to cause (an electric current) to alternate at a high frequency. </DL>
<A NAME="oscillation">
<B>oscillation, </B>noun.<DL COMPACT><DD><B> 1. </B>the fact or process of swinging to and fro like a pendulum. <DD><B> 2. </B>a single swing of a vibrating body. <BR> <I>Ex. Each oscillation of the pendulum takes one second.</I> <DD><B> 3. </B>(Physics.) <DD><B> a. </B>the variation of a quantity from one limit to another, such as the voltage of an alternating current. <BR> <I>Ex. Oscillations may be sustained in a circuit if some provision is made for returning energy at the same rate as it is removed (Sears and Zemansky).</I> <DD><B> b. </B>a single swing from one limit to another. <DD><B> c. </B>an electric wave. </DL>
<A NAME="oscillator">
<B>oscillator, </B>noun.<DL COMPACT><DD><B> 1. </B>a person or thing that oscillates. <DD><B> 2. </B>a device which converts direct current into alternating current of a particular frequency. The oscillator in a radio transmitting apparatus is a vacuum tube which produces the carrier wave for a radio signal. <BR> <I>Ex. It is also proposed to use a number of electric oscillators to provide acceleration (A. W. Haslett).</I> </DL>
<A NAME="oscillatory">
<B>oscillatory, </B>adjective.<DL COMPACT><DD> oscillating. <BR> <I>Ex. The small oscillatory movements of a fixating eye have been observed.</I> </DL>
<A NAME="oscillogram">
<B>oscillogram, </B>noun.<DL COMPACT><DD> a record made by an oscillograph. <BR> <I>Ex. An oscillogram ... pictures the slightest flaw that anxious eyes and modern microscopes can see (New York).</I> </DL>
<A NAME="oscillograph">
<B>oscillograph, </B>noun.<DL COMPACT><DD> an instrument for recording electric oscillations, as of currents and voltages. <BR> <I>Ex. The electrical potentials can be ... then recorded either photographically or by an ink-writing oscillograph (Floyd and Silver).</I> </DL>
<A NAME="oscillographic">
<B>oscillographic, </B>adjective.<DL COMPACT><DD> of or produced by an oscillograph. adv. <B>oscillographically.</B> </DL>
<A NAME="oscillography">
<B>oscillography, </B>noun.<DL COMPACT><DD> the recording of electric oscillations with an oscillograph. </DL>
<A NAME="oscilloscope">
<B>oscilloscope, </B>noun.<DL COMPACT><DD> (Electricity.) an instrument for representing the oscillations of a varying voltage or current on the fluorescent screen of a cathode-ray tube. </DL>
<A NAME="oscilloscopic">
<B>oscilloscopic, </B>adjective.<DL COMPACT><DD> of or produced by an oscilloscope. adv. <B>oscilloscopically.</B> </DL>
<A NAME="oscine">
<B>oscine, </B>noun, adjective,<DL COMPACT><DD><I>noun </I> any one of a large suborder of perching birds that have well-developed vocal organs and usually sing. <DD><I>adj. </I> of or belonging to this group of birds. </DL>
<B>oscitation, </B>noun.<DL COMPACT><DD><B> 1. </B>the act of gaping or yawning; drowsiness. <DD><B> 2. </B>(Figurative.) inattention. </DL>
<A NAME="oscoumbrian">
<B>Osco-Umbrian, </B>adjective, noun.<DL COMPACT><DD><I>adj. </I> of or having to do with the group of Italic dialects comprising Oscan and Umbrian. <DD><I>noun </I> this group of dialects. </DL>
<A NAME="oscula">
<B>oscula, </B>noun.<DL COMPACT><DD> plural of <B>osculum.</B> </DL>
