workbench vs work bench

workbench and work bench both are nouns.

Word	Noun	Adjective	Verb	Adverb
workbench	Yes	No	No	No
work bench	Yes	No	No	No

As nouns, workbench and work bench are synonyms defined as:

workbench and work bench: a strong worktable for a carpenter or mechanic

Other synonyms of workbench include bench.

workbench (noun)	work bench (noun)
a strong worktable for a carpenter or mechanic	a strong worktable for a carpenter or mechanic