'armatolos' originates from Modern Greek, specifically the word 'αρματολός (armatolós)', where the element 'armato-' meant 'armed' (related to 'arms').

'armatolos' changed from Byzantine/Medieval Greek usage referring to an 'armed man' and was applied in Ottoman-period Greek to denote these local armed groups; the term entered Western discussions via travel accounts and historiography and appears in English as 'armatolos' (singular) and 'armatoli' (plural).

Initially it meant 'an armed man' or 'armed group'; over time it came to denote the specific institution of locally organized Christian militia in Ottoman Greece.