To go on tick—on ticket. In the seventeenth century, ticket was the ordinary term for the written acknowledgment of a debt, and one living on credit was said to be living on tick. Betting was then, and still is to a great extent, a matter of tick— i.e. entry of particulars in a betting-book. We have an Act of Parliament prohibiting the use of betting tickets: “Be it enacted, that if any person shall play at any of the said games ... (otherwise than with and for ready money), or shall bet on the sides of such as shall play ... a sum of money exceeding 100 at any one time ... upon ticket or credit ... he shall,” etc. (16 Car. II. cap. 16.)
“If a servant usually buy for the master upon tick, and the servant buy some things without the master's order ... the master is liable.” —Chief Justice Holt (Blackstone, chap. xv. p. 468).
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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