soundness

Ⅰ.

sound [1] ► NOUN 1) vibrations which travel through the air or another medium and are sensed by the ear. 2) a thing that can be heard. 3) music, speech, and sound effects accompanying a film or broadcast. 4) an idea or impression conveyed by words.

► VERB 1) emit or cause to emit sound. 2) utter. 3) convey a specified impression: the job sounds great. 4) (sound off) express one's opinions loudly or forcefully.

DERIVATIVES soundless adjective.

ORIGIN Latin sonus.

Ⅱ.

sound [2] ► ADJECTIVE 1) in good condition. 2) based on reason or judgement. 3) financially secure. 4) competent or reliable. 5) (of sleep) deep and unbroken. 6) severe or thorough: a sound thrashing.

► ADVERB ▪ soundly.

DERIVATIVES soundly adverb soundness noun.

ORIGIN Old English.

Ⅲ.

sound [3] ► VERB 1) ascertain the depth of water in (the sea, a lake, etc.) by means of a line or pole or using sound echoes. 2) (sound out) question (someone) discreetly or cautiously as to their opinions or feelings. 3) Medicine examine (the bladder or other internal cavity) with a long surgical probe.

DERIVATIVES sounder noun.

ORIGIN Old French sonder, from Latin sub- 'below' + unda 'wave' .

Ⅳ.

sound [4] ► NOUN ▪ a narrow stretch of water forming an inlet or connecting two larger bodies of water.

ORIGIN Old Norse, 'swimming, strait' ; related to SWIM(Cf. ↑swimmer).