(one's) John Hancock(redirected from their John Hancock)
(one's) John Hancock
slang One's signature. John Hancock, an influential figure in the American Revolution, is known for his especially large and legible signature on the Declaration of Independence. As soon as you put your John Hancock on these papers, you'll be the proud owner of a brand new car! I would never have put my John Hancock on such an unfavorable contract—I think my signature was forged.
Also, John Henry. One's signature, as in Just put your John Hancock on the dotted line. This expression alludes to John Hancock's prominent signature on the Declaration of Independence. The variant simply substitutes a common name for "Hancock." [Mid-1800s]
n. one’s signature. (Refers to the signature of John Hancock, one of the signers of the Declaration of Independence.) Put your John Hancock right here, if you don’t mind.