pup vs whelp

pup and whelp both are nouns.

Word	Noun	Adjective	Verb	Adverb
pup	Yes	No	Yes	No
whelp	Yes	No	Yes	No

As nouns, pup and whelp are synonyms defined as:

As verbs, pup and whelp are synonyms defined as:

pup (noun)	whelp (noun)
young of any of various canines such as a dog or wolf	young of any of various canines such as a dog or wolf
an inexperienced young person

pup (verb)	whelp (verb)
give birth to (a puppy)	give birth to (a puppy)