bug
n.— «Rode five winners on a December 1981 afternoon at New York’s Aqueduct as an apprentice, something not even “The Kid,”” Steve Cauthen—famous and fresh off his Triple Crown triumph aboard Affirmed three years earlier—had managed to accomplish as a “bug,”” the term for inexperienced riders because of the insect-like asterisk next to their names on track programs.» —“Nearly 20 years later, jockey rides again” by Clark Spencer Olympian (Olympia, Washington) Sept. 1, 2007. (source: Double-Tongued Dictionary)