'buckler' originates from Old French, specifically the word 'bocler' (related to 'bouclier'), where the element 'bocle/boucle' referred to the boss or rounded plate of a shield, ultimately from Late Latin 'buccula' meaning 'little cheek' (diminutive of 'bucca' 'cheek').

'buckler' changed from Middle English 'bokeler' (or 'bukeler'), itself from Old French 'bocler'/'bouclier', and eventually became the modern English word 'buckler'.

Initially, it referred to the boss or rounded central plate of a shield and to small shields generally; over time it came to mean specifically a small round shield used in medieval hand-to-hand combat.