subsonic

Meanings

Plural: subsonics

Adjective

(of speed) less than that of sound in a designated medium
- "aircraft flying at subsonic speeds"

Adj

having a frequency too low to be audible
very quiet, almost inaudible
(aviation) less than the speed of sound (in the same medium, and at the same temperature and pressure)
with a Mach number such that 0.3 < Ma < 0.8 (approximately - the exact limits vary between sources)

Noun

an aircraft whose maximum speed is less than the speed of sound

Origin / Etymology

From sub- + sonic.

Antonyms

sonic, supersonic

Scrabble Score: 12

subsonic is a valid Scrabble (US) TWL word
subsonic is a valid Scrabble Word in Merriam-Webster MW Dictionary
subsonic is a valid Scrabble Word in International Collins CSW Dictionary

Words With Friends Score: 16

subsonic is a valid Words With Friends word