poniard

1. (now chiefly historical) A dagger typically having a slender square or triangular blade.Examples: "The sir King ha's wag'd with him six Barbary horses, / against the which he impon'd as I take it, sixe French / Rapiers and Poniards, with their assignes, as Girdle, / Hangers or so[…]."; "You yeoman phevvterer, conduct mee to / The Lady of the manſion, or my poniard / Shall diſemboge thy ſoule."; "One of the tragic authors, finding himself assaulted in the dark, had, by way of poinard, employed upon his adversary's throat a knife which lay upon the table, for the convenience of cutting cheese […]."historical