Inclined to grouse or complain; having a tendency to grumble or express discontent.
From 'grouse' plus '-y' (adjective-forming suffix). Created in colloquial English to describe someone with a complaining disposition or personality.
The word 'grousy' captures something English doesn't have many terms for—the settled, habitual tendency to complain (different from just being temporarily upset or angry on one occasion).
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