noun
plural -knives
[count] a small knife that has a folding blade :pocketknife
a dive in which you bend from the waist and touch your ankles and then straighten out
verb
-knifes; -knifed; -knifing
[no obj] :to bend in the middle like a folding jackknife especially; of a large truck :to have the back part slide out of control toward the front part