digest vs abbreviate

digest is a noun but abbreviate is not a noun.

Word	Noun	Adjective	Verb	Adverb
digest	Yes	No	Yes	No
abbreviate	No	No	Yes	No

As verbs, abbreviate is a hypernym of digest; that is, abbreviate is a word with a broader meaning than digest:

Other hypernyms of digest include abridge, contract, cut, foreshorten, reduce, shorten.

digest (noun)	abbreviate (noun)
something that is compiled (as into a single book or file)
a periodical that summarizes the news

digest (verb)	abbreviate (verb)
make more concise	shorten
systematize, as by classifying and summarizing	reduce in scope while retaining essential elements
become assimilated into the body
soften or disintegrate by means of chemical action, heat, or moisture
soften or disintegrate, as by undergoing exposure to heat or moisture
arrange and integrate in the mind
put up with something or somebody unpleasant
convert food into absorbable substances