sonar vs sub

sonar and sub both are nouns.

Word	Noun	Adjective	Verb	Adverb
sonar	Yes	No	No	No
sub	Yes	No	Yes	No

sonar (noun)	sub (noun)
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	a submersible warship usually armed with torpedoes
	a large sandwich made of a long crusty roll split lengthwise and filled with meats and cheese (and tomato and onion and lettuce and condiments); different names are used in different sections of the United States

sonar (verb)	sub (verb)
	be a substitute