Webster's Revised Unabridged Dictionary · 1913

Cinch

Cinch , noun

[Sp. cincha, from Latin cingere to gird.]

1.
A strong saddle girth, as of canvas. [West. United States]
2.
A tight grip. [Colloquial]

Cinch , transitive verb

1.
To put a cinch upon; to girth tightly. [Western United States]
2.
To get a sure hold upon; to get into a tight place, as for forcing submission. [Slang, United States]

Cinch , intransitive verb

To perform the action of cinching; to tighten the cinch; -- often with up. [Western United States]

Cinch , noun

[Compare cinch a girth, a tight grip, as v., to get a sure hold upon; perh. so named from the tactics used in the game; also compare Sp. cinco five (the five spots of the color of the trump being important cards).]

A variety of auction pitch in which a draw to improve the hand is added, and the five of trumps (called right pedro) and the five of the same color (called left pedro, and ranking between the five and the four of trumps) each count five on the score. Fifty-one points make a game. Called also double pedro and high five.

Cinch , transitive verb

In the game of cinch, to protect (a trick) by playing a higher trump than the five.