yachting cap vs kepi

yachting cap and kepi both are nouns.

Word	Noun	Adjective	Verb	Adverb
yachting cap	Yes	No	No	No
kepi	Yes	No	No	No

As nouns, yachting cap and kepi are synonyms defined as:

Other synonyms of yachting cap include peaked cap, service cap.

yachting cap (noun)	kepi (noun)
a cap with a flat circular top and a visor	a cap with a flat circular top and a visor