'armorbearer' originates from English, specifically the compound of 'armor' and 'bearer'. 'armor' comes from Old French 'armure' ultimately from Latin 'armatura' meaning 'equipment, arms', and 'bearer' derives from Old English 'berere' (from the verb 'beran') meaning 'one who carries'.

'armor' passed from Latin 'armatura' into Old French as 'armure' and into Middle English as 'armour'; 'bearer' comes from Old English 'berere' (related to Proto-Germanic *beraną 'to carry'). The compound 'armor-bearer' appears in Late Middle English/Early Modern English and later as the single word 'armorbearer' or hyphenated 'armor-bearer'.

Initially it referred specifically to someone who literally carried armor or weapons for another; over time it has retained that historical sense but is also used figuratively to mean a close attendant or trusted protector, especially in biblical or ceremonial contexts.