When Middle English
speakers first borrowed sleuth from the Old Norse word slōth, the term referred
to the track of an animal or person. In Scotland, sleuth hund referred to a
kind of bloodhound used to hunt game or track down fugitives from justice. In
19th-century U.S. English, sleuthhound, soon shortened to sleuth, began to be
used for a detective. From there, sleuth slipped into verb use to apply to what
a sleuth does.
