Full of gladness; completely happy or delighted.
From 'glad' plus '-ful' suffix meaning full of; a compound formed in Middle English following the productive pattern of '-ful' adjectives.
While 'gladful' isn't common today, its existence shows that English speakers once loved stacking meaning-units together—'glad-full' literally means overflowing with gladness, which is more vivid than just saying 'happy.'
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