tick-tacker n. at a horse track, a person (often a tout) who communicates information to others by hand signals. (source: Double-Tongued Dictionary)
Further reading
When Marilyn from Boston, Massachusetts, used the expression Them’s the berries! with neighbors in her hometown of nearby Arlington, Massachusetts, she was surprised they were unfamiliar with it. The phrase means something like “That’s...
“Are we ready to order yet?” Why do restaurant servers use the word “we” when they’re not eating with you or helping you pay the bill? And a story of Cold War intrigue: A young saxophone player’s clever ruse to smuggle information past KGB...