(A). A piece of knotted rope eighteen inches long for the special benefit of ship boys; a cat-o'-nine-tails.
“Look alive there, lads, or as sure as my name is Sam Weston I'll give the colt to the last man off the deck.” —J. Grant: Dick Rodney, chap. vii.
(A). A barrister who attends a sergeant-at-law at his induction.
“I accompanied the newly-made Chief Baron as his colt.” —Pollock.
“Then Mr. Railey, his colt, delivered his ring to the Lord Chancellor.” —Wynne.
(To). To befool, to gull. (Italian, colto, cheated, befooled.)
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894