afternoon tea vs teatime

afternoon tea and teatime both are nouns.

Word	Noun	Adjective	Verb	Adverb
afternoon tea	Yes	No	No	No
teatime	Yes	No	No	No

As nouns, afternoon tea and teatime are synonyms defined as:

afternoon tea and teatime: a light midafternoon meal of tea and sandwiches or cakes

Other synonyms of afternoon tea include tea.

afternoon tea (noun)	teatime (noun)
a light midafternoon meal of tea and sandwiches or cakes	a light midafternoon meal of tea and sandwiches or cakes