avocation vs pastime

avocation and pastime both are nouns.

Word	Noun	Adjective	Verb	Adverb
avocation	Yes	No	No	No
pastime	Yes	No	No	No

As nouns, pastime is a hypernym of avocation; that is, pastime is a word with a broader meaning than avocation:

avocation: an auxiliary activity
pastime: a diversion that occupies one's time and thoughts (usually pleasantly)

Other hypernyms of avocation include interest, pursuit.

avocation (noun)	pastime (noun)
an auxiliary activity	a diversion that occupies one's time and thoughts (usually pleasantly)