dockhand vs longshoreman

dockhand and longshoreman both are nouns.

Word	Noun	Adjective	Verb	Adverb
dockhand	Yes	No	No	No
longshoreman	Yes	No	No	No

As nouns, dockhand and longshoreman are synonyms defined as:

dockhand and longshoreman: a laborer who loads and unloads vessels in a port

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

dockhand (noun)	longshoreman (noun)
a laborer who loads and unloads vessels in a port	a laborer who loads and unloads vessels in a port