trike vs velocipede

trike and velocipede both are nouns.

Word	Noun	Adjective	Verb	Adverb
trike	Yes	No	No	No
velocipede	Yes	No	No	No

As nouns, trike and velocipede are synonyms defined as:

trike and velocipede: a vehicle with three wheels that is moved by foot pedals

Other synonyms of trike include tricycle.

trike (noun)	velocipede (noun)
a vehicle with three wheels that is moved by foot pedals	a vehicle with three wheels that is moved by foot pedals
	any of several early bicycles with pedals on the front wheel