'euhedral' originates from Greek, specifically the elements 'eu' and 'hedra', where 'eu-' meant 'good, well' and 'hedra' meant 'seat/base/face'.

'euhedral' was coined in scientific/technical usage (via Neo-Latin/Modern Latin formations) by combining Greek elements related to 'hedron' (face/seat) and came into English mineralogical/crystallographic use to describe crystals with well-formed faces.

Initially the Greek elements conveyed the sense of 'well-seated' or 'having a good seat', but in mineralogical usage it evolved to mean 'having well-formed external crystal faces'.