scythe n.

Proto-Indo-European root meaning "to cut." It forms all or part of: bisect; dissect; hacksaw; insect; intersect; resect; saw (n.1) "cutting tool;" Saxon; scythe; secant; secateurs; sect; section; sector; sedge; segment; skin; skinflint; skinny; transect.

It is the hypothetical source of/evidence for its existence is provided by: Hittite shakk- "to know, pay attention to;" Latin secare "to cut," sectio "a cutting, cutting off, division;" Old Church Slavonic seko, sešti "to cut," sečivo "ax, hatchet," Russian seč' "to cut to pieces;" Lithuanian įsėkti "to engrave, carve;" Albanian šate "mattock;" Old Saxon segasna, Old English sigðe "scythe;" Old English secg "sword," seax "knife, short sword;" Old Irish doescim "I cut."

late 14c., senten, originally a hunting term, "to find the scent of, perceive by smell," from Old French sentir "to feel, smell, touch, taste; realize, perceive; make love to," from Latin sentire " to feel, perceive by the senses; give one's opinion or sentiments" (see sense (n.)).

The unetymological -c- appeared 17c., perhaps in this case by influence of ascent, descent, etc., or by influence of science. But such an insertion was a pattern in early Modern English and also yielded scythe and for a time threatened to establish scite and scituate.

Figurative use from 1550s. The transitive sense "impregnate with an odor, make fragrant, perfume" is from 1690s. Related: Scented; scenting.

c. 1300, sioun, "a shoot or twig," especially one for grafting, also figurative, from Old French sion, cion "descendant; shoot, twig; offspring" (12c., Modern French scion, Picard chion), a word of uncertain origin. OED rejects derivation from Old French scier "to saw" (as if originally "a sawing, a cutting") on formal grounds. Perhaps it is a diminutive of a Frankish word, from Proto-Germanic *kidon-, from PIE *geie- "to sprout, split, open" (see chink (n.1) ).

The meaning "an heir, child, a descendant" in English is from mid-14c., a figurative use. The proper spelling would be sion; the -c- in the French word, and hence in the English, is unetymological, as it is in scythe, apparently by influence of Latin scindere "to cut." Fem. form scioness seems to have been used mostly for humorous effect.