Grouchy/ˈɡraʊtʃi/ Definition 1 of 2Pro Tip 1/3Not Just Mornings While 'grouchy in the morning' is common, the term can apply anytime someone is irritable. Even after his nap, Daniel was still grouchy. Pro Tip 2/3Duration Matters 'Grouchy' typically describes a temporary mood, not a permanent personality trait. Sorry for being grouchy; I'm just not myself today. Pro Tip 3/3Grouchy Behavior Grouchy can describe actions that show someone's irritable state, like snapping at people. Her grouchy response to the playful teasing was unexpected.