bad-tempered vs grumpy

bad-tempered and grumpy both are adjectives.

Word	Noun	Adjective	Verb	Adverb
bad-tempered	No	Yes	No	No
grumpy	No	Yes	No	No

As adjectives, bad-tempered and grumpy are synonyms defined as:

Other synonyms of bad-tempered include crabbed, crabby, cross, fussy, grouchy, ill-tempered.

bad-tempered (adjective)	grumpy (adjective)
annoyed and irritable	annoyed and irritable