share vs allocation

share and allocation both are nouns.

Word	Noun	Adjective	Verb	Adverb
share	Yes	No	Yes	No
allocation	Yes	No	No	No

As nouns, allocation is a hypernym of share; that is, allocation is a word with a broader meaning than share:

share: the allotment of some amount by dividing something
allocation: the act of distributing by allotting or apportioning; distribution according to a plan

Other hypernyms of share include allotment, apportioning, apportionment, assignation, parceling, parcelling.

As nouns, allocation is a hyponym of share; that is, allocation is a word with a more specific, narrower meaning than share:

share: assets belonging to or due to or contributed by an individual person or group
allocation: a share set aside for a specific purpose

share (noun)	allocation (noun)
the allotment of some amount by dividing something	the act of distributing by allotting or apportioning; distribution according to a plan
the effort contributed by a person in bringing about a result	(computer science) the assignment of particular areas of a magnetic disk to particular data or instructions
a sharp steel wedge that cuts loose the top layer of soil	a share set aside for a specific purpose
assets belonging to or due to or contributed by an individual person or group
any of the equal portions into which the capital stock of a corporation is divided and ownership of which is evidenced by a stock certificate

share (verb)	allocation (verb)
communicate
give out as one's portion or share
have, give, or receive a share of
use jointly or in common
have in common