Unknown. Possibilities include:
- From the Irish caidhp bháis, meaning death cap (the hood put on someone before they were hanged to death, or the "Black cap" worn by English judges when pronouncing the death sentence).
- From the Scots kye booties, meaning cow boots (the hobble put on cattle to prevent them from straying).
- (Can this(+) etymology be sourced?) From the Hebrew כבש, (kbsh) meaning conquer or tread down.
- (Can this(+) etymology be sourced?) From the Hebrew חבש, (khbsh) meaning to bind or to imprison.
- (Can this(+) etymology be sourced?) Some connection with Turkish bosh meaning empty.
Compare bosh (“nonsense”).
- (dated) Nonsense, bosh. [19th c.]
- (Can we find and add a quotation of Dickens to this entry?)
- (slang) A checking or restraining element. Only used in put the kibosh on.
- (transitive) To decisively terminate.