EXAMPLES FROM THE WEB FOR CINCH
"It's a cinch he don't know about that pill-thrower back in Ohio," added Cal.
"It's a cinch you'll take the front seat," he remarked, laconically.
Old Blake would give him work on his ranch over there, that was a cinch.
If you really want her and will follow the rules I give you, it's a cinch.
Gilbert killed there, the room found bolted, was a cinch for suicide.
They've been jawing away for an hour, trying to settle who gets the cinch.
It wa'n't such a cinch to do, either, for he was a lively old gent on his pins.
The centre of Mr. Cinch's gravity was much too far above his waist.
Their degeneration, as she regarded it, had not begun when she married Mr. Cinch.
Mr. Cinch was quite impressed with the force of this philosophy.
1859, American English, "saddle-girth," from Spanish cincha "girdle," from Latin cingulum "a girdle, a swordbelt," from cingere "to surround, encircle," from PIE root *kenk- (1) "to gird, encircle" (cf. Sanskrit kankate "binds," kanci "girdle;" Lithuanian kinkau "to harness horses"). Replaced earlier surcingle. Sense of "an easy thing" is 1898, via notion of "a sure hold" (1888).