clepsydra vs water clock

clepsydra and water clock both are nouns.

Word	Noun	Adjective	Verb	Adverb
clepsydra	Yes	No	No	No
water clock	Yes	No	No	No

As nouns, clepsydra and water clock are synonyms defined as:

clepsydra and water clock: clock that measures time by the escape of water

Other synonyms of clepsydra include water glass.

clepsydra (noun)	water clock (noun)
clock that measures time by the escape of water	clock that measures time by the escape of water