lacrimal sac vs vesicle

lacrimal sac and vesicle both are nouns.

Word	Noun	Adjective	Verb	Adverb
lacrimal sac	Yes	No	No	No
vesicle	Yes	No	No	No

As nouns, vesicle is a hypernym of lacrimal sac; that is, vesicle is a word with a broader meaning than lacrimal sac:

lacrimal sac: either of the two dilated ends of the lacrimal ducts at the nasal ends of the eyes that fill with tears secreted by the lacrimal glands
vesicle: a small anatomically normal sac or bladderlike structure (especially one containing fluid)

Other hypernyms of lacrimal sac include cyst.

lacrimal sac (noun)	vesicle (noun)
either of the two dilated ends of the lacrimal ducts at the nasal ends of the eyes that fill with tears secreted by the lacrimal glands	a small anatomically normal sac or bladderlike structure (especially one containing fluid)