unsub
n.— «Unsub is shorthand for “unknown subject,” meaning the person believed to have committed the crimes. Nor is it new. There was a 1989 series called Unsub, which followed a government unit investigating serial killers.» —“‘Unsub’ unmasked and other TV queries” by R.D. Heldenfels Akron Beacon Journal (Ohio) Apr. 6, 2006. (source: Double-Tongued Dictionary)
Further reading
Matt from Grand Rapids, Michigan, was puzzled when colleagues kept saying someone had stood up at a wedding, indicating that they’d been a member of the wedding party. The expression stood up in that sense is an Americanism going back about two...
Melissa in Greensboro, North Carolina, has been sparring with the Gen Z members of her family over the shifting meanings of words. Her kids use aesthetic as an adjective to mean “aesthetically pleasing,” as in That’s so aesthetic. They also refer to...