handstamp vs rubberstamp

handstamp is a noun but rubberstamp is not a noun.

Word	Noun	Adjective	Verb	Adverb
handstamp	Yes	No	Yes	No
rubberstamp	No	No	Yes	No

As verbs, handstamp and rubberstamp are synonyms defined as:

handstamp and rubberstamp: stamp with a rubber stamp, usually an indication of official approval on a document

handstamp (noun)	rubberstamp (noun)
a stamp (usually made of rubber) for imprinting a mark or design by hand

handstamp (verb)	rubberstamp (verb)
stamp with a rubber stamp, usually an indication of official approval on a document	approve automatically
	stamp with a rubber stamp, usually an indication of official approval on a document