X-acto knifePronunciation: /ɪgˈzaktəʊ/Definition of X-acto knife noun North American trademark a utility knife with a very sharp replaceable blade: my T-square, my X-acto knife, my blue pencilOrigin: 1940s: respelling of the adjective exact + -oX-acto knife in other Oxford dictionaries Definition of X-acto knife in the US English dictionary
