slaphappy vs happy-go-lucky

slaphappy and happy-go-lucky both are adjectives.

Word	Noun	Adjective	Verb	Adverb
slaphappy	No	Yes	No	No
happy-go-lucky	No	Yes	No	No

As adjectives, slaphappy and happy-go-lucky are synonyms defined as:

Other synonyms of slaphappy include carefree, devil-may-care, freewheeling, harum-scarum.

slaphappy (adjective)	happy-go-lucky (adjective)
dazed from or as if from repeated blows	cheerfully irresponsible
cheerfully irresponsible