Which word best describes the meaning of curmudgeonly?

Which word is a good synonym for curmudgeonly?

The answers are explained below.

Explanation:

Curmudgeonly is defined as bad-tempered or negative, specially when referring to an old person. For the first answer, the answer would be bad-tempered. Another option is irritable.

According to Merriam-Webster Dictionary, some good synonyms would be bear or bellyacher or grouch.