veteran vs old hand

veteran and old hand both are nouns.

Word	Noun	Adjective	Verb	Adverb
veteran	Yes	Yes	No	No
old hand	Yes	No	No	No

As nouns, veteran and old hand are synonyms defined as:

veteran and old hand: an experienced person who has been through many battles; someone who has given long service

Other synonyms of veteran include old-timer, old stager, oldtimer, stager, warhorse.

veteran (noun)	old hand (noun)
an experienced person who has been through many battles; someone who has given long service	an experienced person who has been through many battles; someone who has given long service
a person who has served in the armed forces
a serviceman who has seen considerable active service

veteran (adjective)	old hand (adjective)
rendered competent through trial and experience