mark (one's) card

(redirected from mark their card)

mark (one's) card

To alert one to pertinent information about something or someone; to tip one off. Shortly after I started, one of my coworkers marked my card about the boss's tendency to give very harsh criticism.
See also: card, mark

mark someone's card

give someone information. informal
This idiom, which dates from the mid 20th century, derives from the world of horse racing. The card is a race card , the list of runners at a race meeting, so to mark someone's card is to give them tips for possible winners.
See also: card, mark
References in periodicals archive ?
And they must deflect the efforts of those unsportsmanlike players who would mark their cards.
THE way bingo players mark their cards can tell a lot about their personality, according to new research.
A caller would pull numbered discs from a cigar box, and players would mark their cards with dried beans, yelling "Beano!" if they won.