"Any soft, ropy, glutinous, or viscous substance" [Century Dictionary], Old English slim "soft mud," from Proto-Germanic *slimaz (source also of Old Norse slim, Old Frisian slym, Dutch slijm "slime, phlegm," German Schleim "slime"), which is probably related to Old English lim "birdlime; sticky substance."
This is from a PIE root *(s)lei- "slimy, sticky, slippery" (source also of Sanskrit linati "sticks, stays, adheres to; slips into, disappears;" Russian slimak "snail;" Old Church Slavonic slina "spittle;" Old Irish sligim "to smear," leinam "I follow," literally "I stick to;" Welsh llyfn "smooth;" Greek leimax "snail," limne "marsh, pool, lake," alinein "to anoint, besmear;" Latin limus "slime, mud, mire," linere "to daub, besmear, rub out, erase").
As an insult to a person from mid-15c. Figuratively, of anything clinging and offensive, 1570s. Slime-mold, common name for a type of fungi, is from 1880.
1620s, "to cover with or as with slime," from slime (n.). Intransitive sense of "become slimy" is by 1842. Related: Slimed; sliming.
"oily liquid for external application," early 15c., a term in medicine, from Late Latin linimentum "a soft ointment," from Latin linire, collateral form of earlier linere "to daub, smear," from PIE root *(s)lei- "slime, slimy, sticky" (see slime (n.)).
"pertaining to slugs," 1650s, with -ous + Latin limax (genitive limacis) "snail, slug," from Greek leimax, from PIE root *(s)lei- "slime" (see slime (n.)). The Greek word is cognate with Russian slimák "snail," Lithuanian sliekas "earthworm," and the first element in Old English slaw-wyrm "slow-worm."
rhetorical figure in which an affirmative is expressed by the negative of its contrary ("no laughing matter"), from Greek litotes "plainness, simplicity," from litos "smooth, plain," also "frugal, small, meager," and, of style, "simple, unadorned," from PIE root *(s)lei- "slimy, sticky, slippery" (hence "smooth"); see slime (n.).
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.
word-forming element used scientifically, "of or pertaining to lakes and fresh water," from Greek limne "pool of standing water, tidal pool, marsh, lake," a word of uncertain origin; the most likely guess is that it is related to Latin limus "mud," from PIE root *(s)lei- "slime" (see slime (n.)), via the notion of "moistness, standing water" [Beekes].
"destroy, eradicate," 1530s, from Latin deletus, past participle of delere "destroy, blot out, efface," from delevi, originally perfective tense of delinere "to daub, erase by smudging" (as of the wax on a writing table), from de "from, away" (see de-) + linere "to smear, wipe," from PIE root *(s)lei- "slime, slimy, sticky" (see slime (n.)). In English, specifically in reference to written matter from c. 1600. Related: Deleted; deleting.
Middle English sliken "to smooth, polish," from Old English -slician (in nigslicod "newly made sleek"), from Proto-Germanic *slikojan, from *slikaz "sleek, smooth" (source also of Old Norse slikr "smooth," Old High German slihhan "to glide," German schleichen "to creep, crawl, sneak," Dutch slijk "mud, mire"). This is reconstructed to be from PIE *sleig- "to smooth, glide, be muddy, spread," from root *(s)lei- "slimy" (see slime (n.)). Related: Slicked; slicking.