Old English sliefe (West Saxon), slefe (Mercian) "arm-covering part of a garment," probably literally "that into which the arm slips," from Proto-Germanic *slaubjon (source also of Middle Low German sloven "to dress carelessly," Old High German sloufen "to put on or off"). Related to Old English slefan, sliefan "to slip on (clothes)" and slupan "to slip, glide," from PIE root *sleubh- "to slide, slip."
Compare slipper, Old English slefescoh "slipper," slip (n.2) "woman's garment," and expression slip into "dress in." Mechanical sense is attested from 1864. Meaning "the English Channel" translates French La Manche, literally "the sleeve" (from Old French manche "a sleeve," also "a handle," from Latin manicae "long sleeves of a tunic;" see manacle (n.)).
To have something up one's sleeve is recorded from c. 1500 (large sleeves formerly doubled as pockets); to have a card (or ace) up one's sleeve in the figurative sense "have a hidden resource" is from 1863; the cheat itself is mentioned by 1840s. To wear one's heart on (one's) sleeve is from "Othello" (1604).
1530s, "lascivious," from Latin lubricus "slippery, slimy, smooth," figuratively "seductive," from suffixed form of PIE root *sleubh- "to slip, slide" (see sleeve). Literal meaning "slippery, oily" is from 1650s in English; figurative sense of "shifty, elusive" is from 1640s. Also lubricious (1580s).
1590s, "go in an oblique direction," from earlier adjective meaning "slanting" (c. 1500), probably from Middle English aslope (adv.) "on the incline" (late 15c.), from Old English *aslopen, past participle of aslupan "to slip away," from a- "away" + slupan "to slip" (see sleeve). From 1709 as "to be in a slanting position;" transitive sense "place in a slanting position" is from c. 1600. Related: Sloped; sloping.
in various senses from slip (v.). Meaning "act of slipping" is from 1590s. Meaning "mistake, minor fault, blunder" is from 1610s. Sense of "woman's sleeveless garment" (1761) is from notion of something easily slipped on or off (compare sleeve). To give (someone) the slip "escape from" is from 1560s. Meaning "landing place for ships" is mid-15c.; more technical sense in ship-building is from 1769. Slip of the tongue is 1725 (from Latin lapsus linguae); slip of the pen (Latin lapsus calami) is 1650s.
late 14c., "loose outer garment," perhaps from Old English oferslop "surplice," which seems to be related to Middle Dutch slop, Old Norse sloppr (either of which also might be the source of the Middle English word), perhaps all from Proto-Germanic *slup-, from PIE root *sleubh- "to slide, slip" on the notion of a garment one "slips" on or into (compare sleeve). Sense extended generally to "clothing, ready-made clothing" (1660s), usually in plural slops. Hence, also, slop-shop "shop where ready-made clothes are sold" (1723).
Proto-Indo-European root meaning "to slide, slip."
It forms all or part of: cowslip; lubric; lubricant; lubricate; lubricity; lubricous; sleeve; slip (n.3) "potter's clay;" sloop; slop (n.1) "semiliquid refuse;" slop (n.2) "loose outer garment;" sloven.
It is the hypothetical source of/evidence for its existence is provided by: Latin lubricus "slippery, slimy, smooth," lubricare "make slippery or smooth;" Middle Dutch slupen "to glide;" Gothic sliupan "to creep, slide;" Old English slyppe "dung."
Old English smoc "garment worn by women, corresponding to the shirt on men," from Proto-Germanic *smukkaz (source also of Old Norse smokkr "a smock," but this is perhaps from Old English; Old High German smoccho "smock," a rare word; North Frisian smok "woman's shift," but this, too, perhaps from English).
Klein's sources, Barnhart and the OED see this as connected to a group of Germanic sm- words having to do with creeping or pressing close, such as Old Norse smjuga "to creep (through an opening), to put on (a garment)," smuga "narrow cleft to creep through; small hole;" Old Swedish smog "a round hole for the head;" Old English smugan, smeogan "to creep," smygel "a burrow." Compare also German schmiegen "to cling to, press close, nestle;" and Schmuck "jewelry, adornments," from schmucken "to adorn," literally "to dress up."
Watkins, however, traces it to a possible Germanic base *(s)muk- "wetness," figuratively "slipperiness," from PIE root*meug- "slimy, slippery" (see mucus). Either way, the original notion, then, seems generally to have been "garment one creeps or slips into," by the same pattern that produced sleeve and slip (n.2).
Now replaced by euphemistic shift (n.2); smock was the common word down to 18c., and was emblematic of womanhood generally, as in verb smock "to render (a man) effeminate or womanish" (1610s); smocker "man who consorts with women" (18c.); smock-face "person having a pale, effeminate face" (c. 1600). A smock-race (1707) was an old country pastime, a foot-race for women and girls with a smock as a prize. Modern meaning "woman's or child's loose dress or blouse" is from 1907; sense of "loose garment worn by artists over other clothes" is from 1938.