slaphappy vs devil-may-care

slaphappy and devil-may-care both are adjectives.

Word	Noun	Adjective	Verb	Adverb
slaphappy	No	Yes	No	No
devil-may-care	No	Yes	No	No

As adjectives, slaphappy and devil-may-care are synonyms defined as:

Other synonyms of slaphappy include carefree, freewheeling, happy-go-lucky, harum-scarum.

slaphappy (adjective)	devil-may-care (adjective)
dazed from or as if from repeated blows	cheerfully irresponsible
cheerfully irresponsible	marked by a carefree unconventionality or disreputableness