longshoreman vs labourer

longshoreman and labourer both are nouns.

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

As nouns, labourer is a hypernym of longshoreman; that is, labourer is a word with a broader meaning than longshoreman:

longshoreman: a laborer who loads and unloads vessels in a port
labourer: someone who works with their hands; someone engaged in manual labor

Other hypernyms of longshoreman include jack, laborer, manual laborer.

longshoreman (noun)	labourer (noun)
a laborer who loads and unloads vessels in a port	someone who works with their hands; someone engaged in manual labor