shears n.

also *ker-, Proto-Indo-European root meaning "to cut."

It forms all or part of: bias; carnage; carnal; carnation; carnival; carnivorous; carrion; cenacle; charcuterie; charnel; corium; cortex; crone; cuirass; currier; curt; decorticate; excoriate; incarnadine; incarnate; incarnation; kirtle; scabbard; scar (n.2) "bare and broken rocky face of a cliff or mountain;" scaramouche; scarf (n.2) "connecting joint;" scarp; score; scrabble; scrap (n.1) "small piece;" scrape; screen; screw; scrimmage; scrofula; scrub (n.1) "low, stunted tree;" scurf; shard; share (n.1) "portion;" share (n.2) "iron blade of a plow;" sharp; shear; shears; sheer (adj.) "absolute, utter;" shirt; shore (n.) "land bordering a large body of water;" short; shrub; skerry; skirmish; skirt.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit krnati "hurts, wounds, kills," krntati "cuts;" Hittite karsh- "to cut off;" Greek keirein "to cut, shear;" Latin curtus "short," caro (genitive carnis) "flesh" (originally "piece of flesh"); Lithuanian skiriu, skirti "to separate;" Old English sceran, scieran "to cleave, hew, cut with a sharp instrument;" Old Irish scaraim "I separate;" Welsh ysgar "to separate," ysgyr "fragment."

"pair of shears of medium or small size," late 14c., sisoures, also cisours, sesours, cisurs, etc., from Old French cisoires (plural) "shears," from Vulgar Latin *cisoria (plural) "cutting instrument," from *cisus (in compounds such as Latin excisus, past participle of excidere "to cut out"), ultimately from Latin caedere "to cut" (from PIE root *kae-id- "to strike").

The spelling was highly uncertain before 20c. The forms with sc- are from 16c., by influence of Medieval Latin scissor "tailor," in classical Latin "carver, cutter," from past-participle stem of unrelated scindere "to split."

Usually with pair of (attested from c. 1400) when indication of just one is required, but a singular form without the -s occasionally was used (cysowre, mid-15c., but Middle English Compendium reports that is "only in glossaries"). In Scotland, shears (the native word) answers for all sizes, according to OED; but in England generally that word is used only for those too large to be worked by one hand. Sense in wrestling, "a grip with the legs or ankles," is by 1904. In reference to a type of swimming kick, from 1902 (the image itself is from 1880s). Oh scissors! was a 19c. exclamation of impatience or disgust (1843).

1610s, "act of clipping, result of shaving," also as a unit of measure of the age of a sheep, from shear (v.). Also see shears, which is much older. The scientific and mechanical use in reference to a type of transverse strain is attested from 1850.