Slimy

wiktionary

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From Middle English slymy, slimi, either derived from the noun Old English slīm or an unattested *slīmiġ, replacing Old English slipig(“slippy”). Equivalent to slime +‎ -y. Cognate with Dutch slijmig, slijmerig(“slimy”), German schleimig(“slimy; smarmy”), Swedish slemmig(“slimy”).

etymonline

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slimy (adj.)

late 14c., "covered with slime; of the nature of slime," from slime (n.) + -y (2). Similar formation in Middle Dutch slimich, Dutch slijmig, German schleimig. Figurative sense of "morally repulsive" is first attested 1570s. Related: Slimily; sliminess.