Full of glee; joyful, merry, and delighted.
Formed from 'glee' plus the suffix '-some' (Old English '-sum' meaning 'full of' or 'characterized by'). The '-some' suffix appears in many adjectives like 'lonesome,' 'awesome,' and 'handsome,' all indicating a quality or state.
The suffix '-some' is wonderfully productive in English—it lets us quickly create new adjectives meaning 'full of' something. So 'gleesome' means 'full of glee,' just as 'lonesome' means 'full of loneness' and 'awesome' means 'full of awe.' It's an old suffix that still works perfectly!
Complete word intelligence in one call. Free tier — 50 lookups/day.