'unfringed' is formed from the negative prefix 'un-' (Old English 'un-', meaning 'not') combined with 'fringe', which comes from Old French 'fringe' meaning 'tassel' or 'border' (ultimately of Germanic origin).

'fringe' entered English from Old French 'fringe' (12th–13th century) and became Middle English 'fringe'; the prefix 'un-' (Old English) was later attached to form the adjective 'unfringed' meaning 'not fringed'.

Originally 'fringe' meant 'a tassel or border', and this basic sense has persisted; 'unfringed' has consistently meant 'without such a border or fringe'.