pennon
Pennon (noun) means a narrow flag, often pointed or split at the end, once flown from a knight's lance or helmet, and later from a lancer regiment's weapon.
Etymology
The word comes from Late Middle English pennon, penoun (“long narrow flag attached to a lance or used in other contexts; one who bears a pennon, knight bachelor; plume of feathers; strip around the edge of a shield”). This came from Anglo-Norman penun (“feather of an arrow”), penoun (“flag attached to a lance”), Middle French pennon, penoun, and Old French penon (“flag attached to a lance”) (modern French pennon), themselves formed from penne (“feather; wing”) and -on (diminutive suffix). Penne was inherited from Latin penna (“feather (especially a flight feather), pinion; wing”), which goes back ultimately to Proto-Indo-European *peth₂- (“to spread out; to fly (in the sense of spreading out wings)”).