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sonar

/ˈsoʊnɑr/

Underwater sound-based detection and ranging system

From O.English sound (Audible vibration or acoustic signal) + Latin navigation (The steering or directing of a vessel) + O.French ranging (Arranging).

noun
adjective
sound
Old English
sund
Sound; the act or result of making noise
Middle English
sound
Audible vibration or noise
Modern English
sound
Acoustic signal, especially one used for detection
navigation
Latin
nāvigātiō
Voyaging or sailing; from nāvigāre, “to sail”
French
navigation
The practice of steering or directing a vessel
Modern English
navigation
Planning and controlling a course
ranging
Old French
rengier
To arrange in a row or line
Middle English
range
A line, series, or extent of movement
Modern English
ranging
Measuring distance or determining position
Combined
SONAR
A 1946 English acronym formed from sound navigation ranging, modeled on radar.
Modern English
sonar
A system or technique that uses underwater sound pulses and echoes to locate, identify, or measure objects.
Modern English
sonar
“

In 1946, engineers needed a name for a machine that listened beneath the waves, so they clipped three functional words together: sound navigation ranging. The result, SONAR, was deliberately built on the pattern of RADAR, another crisp technical acronym that had already entered public life. Its method is wonderfully simple in outline: send a sharp sound pulse into dark water, wait for the returning echo, and turn the delay into distance. That little underwater “ping” has a cousin in modern computing, where pinging a server likewise means sending a signal and waiting for its reply. So sonar is less an ancient word than a 1940s linguistic machine—three ordinary English-looking parts welded into one name for hearing where human eyes cannot see.

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