ashtray vs receptacle

ashtray and receptacle both are nouns.

Word	Noun	Adjective	Verb	Adverb
ashtray	Yes	No	No	No
receptacle	Yes	No	No	No

As nouns, receptacle is a hypernym of ashtray; that is, receptacle is a word with a broader meaning than ashtray:

ashtray (noun)	receptacle (noun)
a receptacle for the ash from smokers' cigars or cigarettes	a container that is used to put or keep things in
	an electrical (or electronic) fitting that is connected to a source of power and equipped to receive an insert
	enlarged tip of a stem that bears the floral parts