black-collar

adjective4

1. •
   Relating to coalminers and oil workers.
2. •
   (slang) Relating to creative work.

   • In Helsinki, the inner-city workers' housing which was once uniformly red, now occupied by ‘black-collar’ workers—creative industry types who wear a T-shirt to work—votes solidly green. — 2012
3. •
   (rare) Of or pertaining to employment in the black market; that is, to engagement in illicit trade or distribution of untaxed goods and services.

   • Rewards necessarily drop for the former — not only because their numbers increase relatively but also because their output per man-hour does not rise as rapidly as that of the black-collar worker. — 1946
4. •
   (rare) Relating to the clergy.