pousse-cafe vs liqueur

pousse-cafe and liqueur both are nouns.

Word	Noun	Adjective	Verb	Adverb
pousse-cafe	Yes	No	No	No
liqueur	Yes	No	No	No

As nouns, liqueur is a hypernym of pousse-cafe; that is, liqueur is a word with a broader meaning than pousse-cafe:

pousse-cafe: small drink served after dinner (especially several liqueurs poured carefully so as to remain in separate layers)
liqueur: strong highly flavored sweet liquor usually drunk after a meal

Other hypernyms of pousse-cafe include cordial.

pousse-cafe (noun)	liqueur (noun)
small drink served after dinner (especially several liqueurs poured carefully so as to remain in separate layers)	strong highly flavored sweet liquor usually drunk after a meal