Gunk

Full definition of gunk

(countable and uncountable; plural gunks)

(uncountable, informal) dirt or grime; any vague or unknown substanceI washed all the gunk off the light fixture, and found that it was white, not brown.
(uncountable) A subculture of 21st century American males, combining elements of modern gothic culture with punk rock.
(countable) A member of the gunk subculture.