keen -
having a sharp cutting edge or point; "a keen blade"
sharp having or made by a thin edge or sharp point; suitable for cutting or piercing; "a sharp knife"; "a pencil with a sharp point"
keen -
having or demonstrating ability to recognize or draw fine distinctions; "an acute observer of politics and politicians"; "incisive comments"; "icy knifelike reasoning"; "as sharp and incisive as the stroke of a fang"; "penetrating insight"; "frequent penetrative observations"
keen -
painful as if caused by a sharp instrument; "a cutting wind"; "keen winds"; "knifelike cold"; "piercing knifelike pains"; "piercing cold"; "piercing criticism"; "a stabbing pain"; "lancinating pain"