A long blade, not a sickle
A scythe is a hand tool for mowing grass or grain: a long, curved blade fixed at an angle to a long handle and swung in a wide arc. English treats it as distinct from the sickle, a smaller, short-handled blade used with one hand. In older military writing the same noun can also mean a curved blade once mounted on a war chariot. As a verb it means to cut with that sweeping motion, or to slice through as if with one.
Inherited, not borrowed
The origin of the word scythe is native English, not a borrowing from French or Latin. Speakers already had it in Old English, written sīþe, sīgþe, or the earlier-looking form sigdi, as a masculine noun for a mowing blade. Middle English kept the inherited shape as sithe, sythe, and sith. Standard dictionaries that date first English use place the noun before the twelfth century, and the Old English record itself reaches into the period before 900. The language did not need to import a name for a tool already in the fields.
Germanic root, Indo-European cut
That Old English noun comes down from Proto-West Germanic *sigiþi and, behind that, Proto-Germanic *sigiþiz. Other reconstructions write *sigiþō or *segitho; the small spelling differences among handbooks do not change the picture. The reconstructed sense is a sickle or cutting implement, not yet the modern two-handed hay tool as a separate category. The formation sits beside the Germanic word for a saw. English saw, from Old English sagu, is a relative, as are Old English secg for a sword and seax for a knife. The deeper root is Proto-Indo-European *sek-, a verb meaning to cut. Latin secare belongs to the same family, which is why later English words such as section feel thematically close even though they arrived by another route.
Cognates still map that old neighborhood. Middle Low German had segede. Middle Dutch had sichte, continued in Dutch zicht for a sickle. German Sense and Dutch zeis name the long-handled tool that English now calls a scythe, but they are slightly more distant cousins rather than straight matches of the Old English form. Old Norse sigðr, with related northern forms, lined up with the English word; Icelandic sigður and Norwegian Nynorsk sigd still mean a sickle. Old High German segensa and Old Saxon segasna point the same way. The family agrees on cutting. It does not always agree on whether the blade is the short hook or the long swing.
The silent letter
The striking change in English is not a new core meaning but a new spelling. The tool remained a mowing blade. What shifted is the written form. Early in the fifteenth century a silent c was inserted, producing scythe. The earliest surviving example of that sc- spelling is an English word sitting inside a Latin document. The extra letter does not reflect pronunciation and does not mean the noun was taken from Latin. Writers associated the native word with Latin scissor, a cutter or carver, and with scindere, a verb for splitting or cutting. Dictionary accounts treat this as a pseudo-etymological link: the look of a Latin cutting word was laid over a Germanic noun. The same unetymological c appears in English scent and scion. French scier, a verb for sawing, is a parallel false spelling from sier. The inserted letter never became a sound. The usual pronunciation is still the older one, with a voiced th, though some accents use a voiceless th.
Old English glosses already treat the inherited noun as a mowing implement, sometimes matching Latin falx. Modern English later drew a firmer line between sickle and scythe as two tools. That is a later, practical split in the living language, not proof that the Old English word named only the long-handled form. Where sources differ slightly on whether the oldest sense is better labeled sickle or scythe, the gap is real and small: the Germanic word covered a cutting blade for plants, and English later divided the names.
From noun to verb
The verb is younger and homemade. It is conversion from the noun, first recorded in the late 1500s. The earliest dated use often cited is 1574, in John Baret’s Alvearie, in an intransitive sense: to use a scythe. By the 1590s it could mean to mow. By the end of the nineteenth century it could also describe moving with that wide sweep. Figurative cutting followed the tool into later prose: a tackle that scythes a runner down, or fragments that scythe through a deck. Since the Middle Ages, personifications of Time and Death have carried the blade, so the noun also stands for an impersonal force that harvests lives. That image is cultural overlay. It did not replace the farming sense.
The silent letter is the fingerprint worth keeping. English did not take this noun from Latin. It inherited a Germanic cutting-name, then dressed it in a Latinate sc- because the native word had been pulled into the orbit of school Latin for cutting. Dutch zicht still looks much closer to Middle English sithe than the modern English spelling does. The c is decoration. The history sits in the older consonants that farmers were already using before anyone added it.