Turk's-head \Turk's"-head`\, n. 1. (Naut.) A knot of turbanlike form worked on a rope with a piece of small line. 2. (a) The melon cactus. [West Indies] (b) Any of several species of {Echinocactus}. [California] 3. A long-handled, round-headed broom for sweeping ceilings, etc. [Colloq. or Dial.]