Comparative form of glumpy; more characterized by glumping, sulkiness, or heavy gloominess.
From 'glumpy' + '-er' (comparative suffix). 'Glumpy' itself derives from 'glump' (to sulk or look morose) + '-y' (adjective suffix).
The progression 'glumpy,' 'glumpier,' 'glumpiest' shows how regional dialect words can develop their own full comparative systems—British English speakers used these to describe teenagers in particular.
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