dockworker vs dock worker

dockworker and dock worker both are nouns.

Word	Noun	Adjective	Verb	Adverb
dockworker	Yes	No	No	No
dock worker	Yes	No	No	No

As nouns, dockworker and dock worker are synonyms defined as:

dockworker and dock worker: a laborer who loads and unloads vessels in a port

Other synonyms of dockworker include dock-walloper, docker, dockhand, loader, longshoreman, lumper, stevedore.

dockworker (noun)	dock worker (noun)
a laborer who loads and unloads vessels in a port	a laborer who loads and unloads vessels in a port