Pioneer comes from Middle French pionnier, a foot soldier who dug trenches ahead of the army. From Medieval Latin pedōnem (foot soldier), Latin pēs (foot), PIE *ped-. The leap from 'lowly trench-digger' to 'heroic explorer' occurred in the 16th–17th centuries. Shares its root with pawn (chess foot soldier) and peon (laborer).
One who goes before others to prepare the way; an early settler or explorer; one who originates a new line of thought or development.
From Middle French 'pionnier' (a foot soldier assigned to dig trenches and clear obstacles ahead of the main army), from Old French 'peonier' (a foot soldier, one who goes on foot), from Medieval Latin 'pedōnem' (accusative of 'pedō,' a foot soldier, a person who walks), from Latin 'pēs' (foot), genitive 'pedis,' from Proto-Indo-European *ped- (foot). The PIE root *ped- is one of the most productive in the language family: it produced Latin 'pedis' (of the foot), giving English 'pedal,' 'pedestrian,' 'pedigree' (a genealogical chart — from French 'pied de grue,' crane's foot, describing the forking lines), 'impede' (to put fetters on the feet), and 'expedite' (to free the feet from fetters). Greek 'pous/podos' (foot) from
Pioneer, pawn, and peon all descend from Medieval Latin pedōnem (foot soldier). In chess, the pawn is expendable infantry. In the military, the pioneer was lowly infantry digging trenches. Over centuries, the pawn stayed low and the pioneer climbed to glory — a rare case where the same root