1knife 
/ˈnaɪf/ noun
plural knives /ˈnaɪf/ noun /ˈnaɪvz/ [count] : a usually sharp blade attached to a handle that is used for cutting or as a weapon
▪ Each dinner guest gets two forks, a knife, and a spoon. ▪ He pulled/drew a knife on me and threatened to stab me with it. — see picture at place setting; see also butter knife, carving knife, palette knife, paring knife, steak knife, utility knife
▪ Each dinner guest gets two forks, a knife, and a spoon. ▪ He pulled/drew a knife on me and threatened to stab me with it. — see picture at place setting; see also butter knife, carving knife, palette knife, paring knife, steak knife, utility knife
like a (hot) knife through butter
informal : very quickly and easily
▪ The bill passed through the senate like a hot knife through butter.
▪ The bill passed through the senate like a hot knife through butter.
the knives are out (for someone)
— used to say that people are ready to blame or punish someone for something often in a way that is unfair ▪ They lost yet another important game, and now the knives are out for their coach.
twist/turn the knife (in the wound)
informal : to say or do things that cause more pain to someone who is already suffering
▪ Any more cuts in government aid to these poor people will be twisting the knife in the wound.
▪ Any more cuts in government aid to these poor people will be twisting the knife in the wound.
under the knife
informal : having a medical operation
▪ I'm going under the knife [=having surgery] tomorrow.
▪ I'm going under the knife [=having surgery] tomorrow.
