n. & v.
n. 1 colloq. a a sure thing; a certainty. b an easy task. 2 a firm hold. 3 esp. US a girth for a saddle or pack.
v.tr. 1 a tighten as with a cinch (cinched at the waist with a belt). b secure a grip on. 2 sl. make certain of. 3 esp. US put a cinch (sense 3) on.
[ Sp. cincha ]