1. A tight curl, twist, or bend in a length of thin material, as one caused by the tensing of a looped section of wire.

2. A painful muscle spasm, as in the neck or back; a crick.

3. A difficulty or flaw that is likely to impede operation, as in a plan or system.

4. A mental peculiarity; a quirk.

5. An unusual or eccentric idea.

6. Slang Peculiarity or deviation in sexual behavior or taste.