1650s, "covered with scurf," from scruff "dandruff, scurf" (late Old English variant of scurf) + -y (2). Generalized sense of "rough and dirty" is from 1871. Related: Scruffily; scruffiness.
a surge of ragged scruffy children
scrotum
scrounge
scrub
scrubby
scruff
scruffy
scrum
scrumptious
scrunch
scruple
scrupulous