'scalene' originates from Greek, specifically the word 'skálēnos' (σκαληνός), where it meant 'uneven' or 'oblique'.

'scalene' passed into Late Latin/Medieval Latin as 'scalenus' and was later adopted into English as 'scalene' (used in geometry and anatomy).

Initially it meant 'uneven'; over time it came to refer specifically to triangles with unequal sides and to the neck muscles named for their unequal lengths.