soundness

Concise Oxford English Dictionary © 2008 Oxford University Press:
sound1

▶noun

• 1 vibrations which travel through the air or another medium and are sensed by the ear.

  ■ a thing that can be heard.

  ■ the area within which something can be heard.

• 2 (also musical sound) sound produced by continuous and regular vibrations, as opposed to noise.

• 3 music, speech, and sound effects accompanying a film or broadcast.

  ■ radio broadcasting as distinct from television.

• 4 an idea or impression conveyed by words.

▶verb

• 1 emit or cause to emit sound.

  ■ utter.

• 2 convey a specified impression when heard.

• 3 (sound off) express one's opinions loudly or forcefully.

• 4 test (the lungs or another body cavity) by noting the sound they produce.

– derivatives
soundless adjective,
soundlessly adverb,
soundlessness noun.

– origin ME soun, from Anglo-Norman Fr. soun (n.), suner (v.), from L. sonus.

Concise Oxford English Dictionary © 2008 Oxford University Press:
sound2

▶adjective

• 1 in good condition.

  ■ financially secure.

  ■ Brit. informal excellent.

• 2 based on reason or judgement.

  ■ competent or reliable.

• 3 (of sleep) deep and unbroken.

• 4 severe: a sound thrashing.

▶adverb soundly.

– derivatives
soundly adverb,
soundness noun.

– origin ME: from OE gesund, of W. Gmc origin.

Concise Oxford English Dictionary © 2008 Oxford University Press:
sound3

▶verb

• 1 ascertain (the depth of water in the sea, a lake, etc.) by means of a line or pole or using sound echoes.

  ■ find the depth of water in (a ship's hold).

• 2 Medicine examine (the bladder or other internal cavity) with a long surgical probe.

• 3 (sound someone out) question someone discreetly or cautiously.

• 4 (especially of a whale) dive steeply to a great depth.

▶noun a long surgical probe, typically with a curved, blunt end.

– derivatives
sounder noun.

– origin ME: from OFr. sonder, based on L. sub- ‘below’ + unda ‘wave’.

Concise Oxford English Dictionary © 2008 Oxford University Press:
sound4

▶noun a narrow stretch of water forming an inlet or connecting two larger bodies of water.

– origin ME: from ON sund ‘swimming, strait’; rel. to swim.