telltale
n.— «The replacement part turns on a little telltale next to the odometer display indicating that the part has been replaced.» —“Re: reprogramming digital odometers” by Mike Griese (magriese@polaris.rchland.ibm.com) Usenet: rec.autos.marketplace Apr. 7, 1995. (source: Double-Tongued Dictionary)
Further reading
Book recommendations and the art of apology. Martha and Grant share some good reads, including an opinionated romp through English grammar, a Spanish-language adventure novel, an account of 19th-century dictionary wars, and a gorgeously illustrated...
The autocomplete function on your phone comes in handy, of course. But is it changing the way we write and how linguists study language? Also, suppose you could invite any two authors, living or dead, to dinner. Who’s on your guest list and...