n. 1 a short-handled farming tool with a semicircular blade, used for cutting corn, lopping, or trimming. 2 anything sickle-shaped, esp. the crescent moon. sickle-bill any of various curlews with a sickle-shaped bill. sickle-cell a sickle-shaped blood-cell, esp. as found in a type of severe hereditary anaemia. sickle-feather each of the long middle feathers of a cock's tail.
[ OE sicol, sicel f. L secula f. secare cut ]