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adjective \ˈsau̇nd\

Simple Definition of sound

  • : in good condition : solid and strong

  • : in good health

  • : free from mistakes : showing good judgment

Full Definition of sound

  1. 1a :  free from injury or diseaseb :  free from flaw, defect, or decay

  2. 2 :  solid, firm; also :  stable

  3. 3a :  free from error, fallacy, or misapprehension <sound reasoning>b :  exhibiting or based on thorough knowledge and experience <sound scholarship>c :  legally valid <a sound title>d :  logically valid and having true premisese :  agreeing with accepted views :  orthodox

  4. 4a :  thoroughb :  deep and undisturbed <a sound sleep>c :  hard, severe <a sound whipping>

  5. 5 :  showing good judgment or sense <sound advice>

sound·ly play \ˈsau̇n(d)-lē\ adverb
sound·ness play \ˈsau̇n(d)-nəs\ noun

Examples of sound

  1. a building of sound construction

  2. The bridge is structurally sound.

  3. a sound mind in a sound body

  4. The tests show that his heart is sound.

  5. She used sound reasoning in making the decision.

  6. She gave us some sound advice.

  7. She has a sound understanding of the system's structure.

  8. The stock market has made a sound recovery.

Origin of sound

Middle English, from Old English gesund; akin to Old High German gisunt healthy

First Known Use: 13th century

Synonym Discussion of sound

healthy, sound, wholesome, robust, hale, well mean enjoying or indicative of good health. healthy implies full strength and vigor as well as freedom from signs of disease <a healthy family>. sound emphasizes the absence of disease, weakness, or malfunction <a sound heart>. wholesome implies appearance and behavior indicating soundness and balance <a face with a wholesome glow>. robust implies the opposite of all that is delicate or sickly <a lively, robust little boy>. hale applies particularly to robustness in old age <still hale at the age of eighty>. well implies merely freedom from disease or illness <she has never been a well person>.

valid, sound, cogent, convincing, telling mean having such force as to compel serious attention and usually acceptance. valid implies being supported by objective truth or generally accepted authority <a valid reason for being absent> <a valid marriage>. sound implies a basis of flawless reasoning or of solid grounds <a sound proposal for reviving the economy>. cogent may stress either weight of sound argument and evidence or lucidity of presentation <the prosecutor's cogent summation won over the jury>. convincing suggests a power to overcome doubt, opposition, or reluctance to accept <a convincing argument for welfare reform>. telling stresses an immediate and crucial effect striking at the heart of a matter <a telling example of bureaucratic waste>.

Rhymes with sound




Simple Definition of sound

  • of sleep : deeply and completely

Full Definition of sound

  1. :  to the full extent :  thoroughly <sound asleep>

14th Century

First Known Use of sound

14th century




Definition of sound

  1. 1a :  a particular auditory impression :  toneb :  the sensation perceived by the sense of hearingc :  mechanical radiant energy that is transmitted by longitudinal pressure waves in a material medium (as air) and is the objective cause of hearing

  2. 2a :  a speech sound <a peculiar r-sound>b :  value in terms of speech sounds <-cher of teacher and -ture of creature have the same sound>

  3. 3 archaic :  rumor, fame

  4. 4a :  meaningless noiseb obsolete :  meaningc :  the impression conveyed :  import

  5. 5 :  hearing distance :  earshot <within sound of your voice>

  6. 6 :  recorded auditory material

  7. 7 :  a particular musical style characteristic of an individual, a group, or an area <the Nashville sound>

Origin of sound

Middle English soun, from Anglo-French son, sun, from Latin sonus, from sonare to sound; akin to Old English swinn melody, Sanskrit svanati it sounds

First Known Use: 13th century




Definition of sound

  • transitive verb
    1. 1a :  to cause to sound <sound a trumpet>b :  pronounce 3a

    2. 2 :  to put into words :  voice

    3. 3a :  to make known :  proclaimb :  to order, signal, or indicate by a sound <sound the alarm>

    4. 4 :  to examine by causing to emit sounds <sound the lungs>

    5. 5 chiefly British :  to convey the impression of :  sound like <that sounds a logical use of resources — Economist>

    6. intransitive verb
    7. 1a :  to make a soundb :  resoundc :  to give a summons by sound <the bugle sounds to battle>

    8. 2 :  to make or convey an impression especially when heard <it sounds good to me> <you sound just like your mother>

    sound·able play \ˈsau̇n-də-bəl\ adjective

    13th Century

    First Known Use of sound

    13th century




    Definition of sound

    1. 1a :  a long broad inlet of the ocean generally parallel to the coastb :  a long passage of water connecting two larger bodies (as a sea with the ocean) or separating a mainland and an island

    2. 2 :  the air bladder of a fish

    Origin of sound

    Middle English, from Old English sund swimming, sea & Old Norse sund swimming, strait; akin to Old English swimman to swim

    First Known Use: 14th century

    Other Oceanography Terms




    Definition of sound

    1. transitive verb
    2. 1 :  to measure the depth of :  fathom

    3. 2 :  to try to find out the views or intentions of :  probe —often used with out

    4. 3 :  to explore or examine (a body cavity) with a sound

    5. intransitive verb
    6. 1a :  to ascertain the depth of water especially with a sounding lineb :  to look into or investigate the possibility <sent commissioners…to sound for peace — Thomas Jefferson>

    7. 2 :  to dive down suddenly —used of a fish or whale

    Origin of sound

    Middle English, from Middle French sonder, from Old French *sonde sounding line, probably from Old English or Middle English sund- (as in Old English sundlīne sounding line) from sund sea

    First Known Use: 15th century




    Definition of sound

    1. :  an elongated instrument for exploring or sounding body cavities

    Origin of sound

    French sonde, from Middle French, literally, sounding line

    First Known Use: 1739

    Seen and Heard

    What made you want to look up sound? Please tell us where you read or heard it (including the quote, if possible).


    February 7, 2016

    a slight offense

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