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WORDNET DICTIONARY
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WORDNET DICTIONARY

Noun sonar has 1 sense

• sonar(n = noun.artifact) asdic, echo sounder - a measuring instrument that sends out an acoustic pulse in water and measures distances in terms of the time for the echo of the pulse to return; "sonar is an acronym for sound navigation ranging"; "asdic is an acronym for antisubmarine detection investigation committee"
is a kind of measuring device, measuring instrument, measuring system, navigational instrument
has parts: pinger, pulse generator
is a part of pigboat, sub, submarine, u-boat

OXFORD DICTIONARY

THESAURUS

sonar

astronavigation, bathometry, bathymetry, celestial navigation, chronometer, coastwise navigation, consolan, dead reckoning, depth sounding, echo sounding, echolocation, fathomage, fathoming, fix, line of position, loran, oceanography, pilotage, plane sailing, point-to-point navigation, radar, radio beacon, radio navigation, sextant, shoran, sofar, sounding, soundings, tables, water

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sonar

Depth

N depth, deepness, profundity, depression, hollow, pit, shaft, well, crater, gulf, bowels of the earth, botttomless pit, hell, soundings, depth of water, water, draught, submersion, plummet, sound, probe, sounding rod, sounding line, lead, bathymetry, sonar, side-looking sonar, bathometer, deep, deep seated, profound, sunk, buried, submerged, subaqueous, submarine, subterranean, subterraneous, subterrene, underground, bottomless, soundless, fathomless, unfathomed, unfathomable, abysmal, deep as a well, bathycolpian, benthal, benthopelagic, downreaching, yawning, knee deep, ankle deep, beyond one's depth, out of one's depth, over head and ears, mark twine, mark twain.

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