day laborer vs labourer

day laborer and labourer both are nouns.

Word	Noun	Adjective	Verb	Adverb
day laborer	Yes	No	No	No
labourer	Yes	No	No	No

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

day laborer: a laborer who works by the day; for daily wages
labourer: someone who works with their hands; someone engaged in manual labor

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

day laborer (noun)	labourer (noun)
a laborer who works by the day; for daily wages	someone who works with their hands; someone engaged in manual labor