postdoc vs postdoctoral

postdoc and postdoctoral both are nouns.

Word	Noun	Adjective	Verb	Adverb
postdoc	Yes	No	No	No
postdoctoral	Yes	Yes	No	No

As nouns, postdoc and postdoctoral are synonyms defined as:

postdoc and postdoctoral: a grant that funds postdoctoral study or research

Other synonyms of postdoc include post doc.

postdoc (noun)	postdoctoral (noun)
a scholar or researcher who is involved in academic study beyond the level of a doctoral degree	a grant that funds postdoctoral study or research
a grant that funds postdoctoral study or research

postdoc (adjective)	postdoctoral (adjective)
	of or relating to study or research that is done after work for the doctoral degree has been completed