<B>acorn, </B>noun.<DL COMPACT><DD> the nut of an oak tree. </DL>
<A NAME="acornbarnacle">
<B>acorn barnacle,</B><DL COMPACT><DD> a barnacle that lives on rocks in the sea. </DL>
<A NAME="acornshell">
<B>acorn shell,</B><DL COMPACT><DD> (British.) a rock barnacle. </DL>
<A NAME="acornsquash">
<B>acorn squash,</B><DL COMPACT><DD> a small, dark-green, edible winter squash resembling an acorn in shape, having yellow or orange flesh. </DL>
<A NAME="acorntube">
<B>acorn tube,</B><DL COMPACT><DD> a small vacuum tube, shaped like an acorn, used at high frequencies, formerly in radios. </DL>
<A NAME="acornworm">
<B>acorn worm,</B><DL COMPACT><DD> a small, wormlike marine animal whose front end looks somewhat like an acorn. </DL>
<A NAME="acorpsperdu">
<B>a corps perdu,</B><DL COMPACT><DD> (French.) impetuously; furiously. </DL>
<A NAME="acosmic">
<B>acosmic, </B>adjective.<DL COMPACT><DD><B> 1. </B>having to do with acosmism. <DD><B> 2. </B>disordered; confused; disharmonious. </DL>
<A NAME="acosmism">
<B>acosmism, </B>noun.<DL COMPACT><DD> the denial of the existence of a universe, or of a universe as distinct from God. noun <B>acosmist.</B> </DL>
<A NAME="acotyledon">
<B>acotyledon, </B>noun.<DL COMPACT><DD> a plant without cotyledons, such as a moss or lichen; cryptogam. </DL>
<A NAME="acotyledonous">
<B>acotyledonous, </B>adjective.<DL COMPACT><DD> having no distinct cotyledons; cryptogamic. </DL>
<A NAME="acouchi">
<B>acouchi, </B>noun, pl. <B>-chis.</B><DL COMPACT><DD> a small rodent related to the guinea pig and agouti, native to Guinea. </DL>
<A NAME="acouchy">
<B>acouchy, </B>noun, pl. <B>-chies.</B> =acouchi.</DL>
<A NAME="acoumeter">
<B>acoumeter, </B>noun.<DL COMPACT><DD> an instrument for measuring keenness of hearing. </DL>
<A NAME="acousma">
<B>acousma, </B>noun, pl. <B>-mas,</B> <B>-mata.</B><DL COMPACT><DD> (Psychology.) the hearing of imaginary sounds; auditory hallucination. </DL>
<A NAME="acoustic">
<B>acoustic, </B>adjective.<DL COMPACT><DD><B> 1. </B>having to do with the sense or the organs of hearing. <DD><B> 2. </B>having to do with the science of sound (acoustics). <DD><B> 3a. </B>of or having to do with sound waves or sound. <DD><B> b. </B>actuated, directed, or controlled by sound waves. <BR> <I>Ex. an acoustic mine.</I> <DD><B> 4. </B>designed to absorb or reduce noise. <BR> <I>Ex. a ceiling of acoustic tile.</I> <DD><B> 5. </B>of, having to do with, or produced on a musical instrument without amplification. <BR> <I>Ex. Paul McCartney authorized a limited 500,000-copy release of "Paul McCartney Unplugged the Bootleg", which documents an all-acoustic concert (Time).</I> adv. <B>acoustically.</B> </DL>
<A NAME="acoustical">
<B>acoustical, </B>adjective. =acoustic.</DL>
<A NAME="acousticalhologram">
<B>acoustical hologram,</B><DL COMPACT><DD> a picture produced by acoustical holography. </DL>
<A NAME="acousticalholography">
<B>acoustical holography,</B><DL COMPACT><DD> holography that uses sound waves instead of laser light to produce a three-dimensional picture. <BR> <I>Ex. Hence, a hologram can be recorded with sound waves and then reconstructed with light. This technique is called acoustical holography (Science Journal).</I> </DL>
<A NAME="acousticcoupler">
<B>acoustic coupler,</B><DL COMPACT><DD> a device for transmitting data over telephone circuits without making an electrical connection. <BR> <I>Ex. Impulses from the keys of an electric typewriter are converted into sound by the acoustic coupler (London Times).</I> </DL>
<A NAME="acousticfeedback">
<B>acoustic feedback,</B><DL COMPACT><DD> (Electronics.) the feedback of sound from the output of a sound system back to the input, such as noise from a loudspeaker reaching the microphone. </DL>
<A NAME="acoustician">
<B>acoustician, </B>noun.<DL COMPACT><DD><B> 1. </B>an expert in acoustics. <DD><B> 2. </B>a person trained in fitting the hard-of-hearing with hearing aids. </DL>
<A NAME="acousticity">
<B>acousticity, </B>noun.<DL COMPACT><DD> acoustic quality or condition. </DL>
<A NAME="acousticmine">
<B>acoustic mine,</B><DL COMPACT><DD> a mine that has a small microphone connected to its trigger, exploded by the sound of the propellers of a vessel passing over or near it; sonic mine. </DL>
<A NAME="acousticnerve">
<B>acoustic nerve,</B><DL COMPACT><DD> an auditory nerve. </DL>
<A NAME="acousticperfume">
<B>acoustic perfume,</B><DL COMPACT><DD> an overlay of nondescript sound to cover up distracting or annoying noises; white noise. <BR> <I>Ex. The most popular form of acoustic perfume, of course, is music (Eugene Raskin).</I> </DL>
<A NAME="acousticphonetics">
<B>acoustic phonetics,</B><DL COMPACT><DD> study of speech sounds by means of acoustic tools and techniques. </DL>
<A NAME="acoustics">
<B>acoustics, </B>noun pl.<DL COMPACT><DD><B> 1. </B>the structural features of an auditorium, hall, or room, that determine how well sounds can be heard or transmitted in it; acoustic qualities. <BR> <I>Ex. The acoustics will be particularly poor, as they invariably are in new auditoriums (Norman Mailer).</I> <DD><B> 2. </B>the science of sound. </DL>
<A NAME="acousticvelocity">
<B>acoustic velocity,</B><DL COMPACT><DD> the rate at which a sound wave travels through a specified medium. </DL>
<A NAME="acousticwave">
<B>acoustic wave,</B> =sound wave.</DL>
<A NAME="acousto">
<B>acousto-,</B><DL COMPACT><DD> (combining form.) <DD><B> 1. </B>of sound or acoustic waves. <BR> <I>Ex. Acoustoelectronics = the study of the conversion of electronic signals into sound waves.</I> <DD><B> 2. </B>acoustic and ____. <BR> <I>Ex. Acousto-optic modulator = acoustic and optic modulator.</I> </DL>
<A NAME="acoustoelectronics">
<B>acoustoelectronics, </B>noun.<DL COMPACT><DD> a branch of electronics dealing with the conversion of electrical signals into a flow of acoustic waves traveling along a solid surface. </DL>
<A NAME="acouvert">
<B>a couvert,</B><DL COMPACT><DD> (French.) sheltered from the weather; covered. </DL>
<A NAME="acp">
<B>ACP</B> (no periods),<DL COMPACT><DD> African, Caribbean, and Pacific countries (group of over 40 nonaligned nations that have a treaty of cooperation with the European Economic Community). </DL>
<A NAME="acquaalta">
<B>acqua alta,</B><DL COMPACT><DD> (Italian.) high water. <BR> <I>Ex. Venetians are quite accustomed to minor attacks of such acqua alta, which, in the spring and fall, frequently invade the lower floors of houses and submerge the famous square under a foot or so (New Yorker).</I> </DL>
<A NAME="acquaint">
<B>acquaint, </B>transitive verb.<DL COMPACT><DD><B> 1. </B>to furnish (a person) with information; make aware; let know; inform. <BR> <I>Ex. Acquaint him with your plans for next summer.</I> (SYN) tell, apprise. <DD><B> 2. </B>to make more or less familiar (with). <BR> <I>Ex. Let me acquaint you with your new duties.</I> (SYN) familiarize. <BR><I>expr. <B>be acquainted with,</B> </I>to be familiar with or know. <BR> <I>Ex. I am acquainted with his plans.</I> <BR><I>expr. <B>become acquainted with,</B> </I>to get to know. <BR> <I>Ex. We became acquainted with our new neighbors.</I> </DL>
<A NAME="acquaintance">
<B>acquaintance, </B>noun, adjective.<DL COMPACT><DD><I>noun </I> <B>1. </B>pl. <B>-ances.</B> a person known to one, but not a close friend. <BR> <I>Ex. We have many acquaintances in our neighborhood.</I> <DD><B> 2. </B><I>no pl.</I> <DD><B> a. </B>knowledge of persons or things gained from experience with them. Acquaintance is more than mere recognition, and less than familiarity or intimacy. <BR> <I>Ex. I have some acquaintance with French, but I do not know it well.</I> <DD><B> b. </B>the state of being acquainted, or of knowing people and being known by them. <BR> <I>Ex. a man of wide acquaintance.</I> <DD><I>adj. </I> committed by an acquaintance. <BR> <I>Ex. Many "acquaintance homicides" involve quarrels between drug cheaters or street gangs (Atlantic). The phrase "acquaintance rape" was coined to describe ... the cases of forced sex between people who already know each other (Time).</I> <BR><I>expr. <B>cultivate the acquaintance of,</B> </I>to try to get to know (someone) well. <BR> <I>Ex. The ambitious young candidate tried to cultivate the acquaintance of the most influential politicians of his state.</I> <BR><I>expr. <B>make the acquaintance of,</B> </I>to get to know. <BR> <I>Ex. My mother soon made the acquaintance of my new teacher. We spent a day or two in making the general acquaintance of the glacier (John Tyndall).</I> <BR><I>expr. <B>scrape acquaintance,</B> </I>to take the trouble to get acquainted. <BR> <I>Ex. Her two dearest friends had contrived to scrape acquaintance without introduction (F. Whishaw).</I> </DL>
<A NAME="acquaintanceship">
<B>acquaintanceship, </B>noun.<DL COMPACT><DD><B> 1. </B>the relation between acquaintances. <BR> <I>Ex. Their acquaintanceship lasted many years.</I> <DD><B> 2. </B>personal knowledge; acquaintance. <BR> <I>Ex. While Interlingua can be read with little difficulty by almost anyone, books are available which will give a formal acquaintanceship with this international language (Science News Letter).</I> </DL>
<A NAME="acquest">
<B>acquest, </B>noun.<DL COMPACT><DD><B> 1. </B>a thing acquired; acquisition. <DD><B> 2. </B>(Law.) property acquired otherwise than by succession. </DL>
<A NAME="acquiesce">
<B>acquiesce, </B>intransitive verb, <B>-esced,</B> <B>-escing.</B><DL COMPACT><DD> to give consent; accept by keeping silent or by not making objections; agree or submit quietly. <BR> <I>Ex. to acquiesce in a decision. We acquiesced in their plan because we could not suggest a better one.</I> (SYN) accede, assent, concur. adv. <B>acquiescingly.</B> </DL>
<A NAME="acquiescence">
<B>acquiescence, </B>noun.<DL COMPACT><DD> consent given without making objections; agreeing or submitting quietly; assent. </DL>
<B>acquire, </B>transitive verb, <B>-quired,</B> <B>-quiring.</B><DL COMPACT><DD><B> 1. </B>to get by one's own efforts or actions. <BR> <I>Ex. He acquired the money for a college education by working summers.</I> (SYN) gain, win, attain. <DD><B> 2. </B>to come to have; get as one's own. <BR> <I>Ex. to acquire land. He acquired a strong liking for sports at camp.</I> (SYN) obtain. <DD><B> 3. </B>to find, take up, and hold. <BR> <I>Ex. This ... robot uses vision to acquire the letters that spell out its name, and arranges them in order (G. I. Robertson).</I> adj. <B>acquirable.</B> noun <B>acquirer.</B> </DL>
