late 14c., slimie, "covered with slime; of the nature of slime," of places, "muddy, marshy, full of silt," from slime (n.) + -y (2). Similar formation in Middle Dutch slimich, Dutch slijmig, German schleimig. The figurative sense of "morally repulsive" is attested from 1570s. Related: Slimily; sliminess.
updated on January 07, 2023