Old English fleax "flax plant; cloth made with flax, linen," from Proto-Germanic *flakhsan (source also of Old Frisian flax, Middle Dutch and Dutch vlas, Old Saxon flas, Old High German flahs, German Flachs), probably from Proto-Germanic base *fleh- "to plait," from PIE root *plek- "to plait." But some connect it with PIE *pleik- (see flay) from the notion of "stripping" fiber to prepare it.

also flax-seed, 1560s, from flax + seed (n.).

"made of flax," mid-15c., from flax + -en (2). As "of the color of flax" (usually with reference to hair) it is attested from 1520s.

mid-14c., from Medieval Latin flasco "container, bottle," from Late Latin flasconem (nominative flasco) "bottle," which is of uncertain origin. A word common to Germanic and Romanic, but it is unclear whether the Latin or Germanic word is the original (or whether both might have got it from the Celts). Those who support a Germanic origin compare Old English flasce "flask, bottle" (which would have become modern English *flash), Old High German flaska, Middle Dutch flasce, German Flasche "bottle." If it is Germanic, the original sense might be "bottle plaited round, case bottle" (compare Old High German flechtan "to weave," Old English fleohtan "to braid, plait"), from Proto-Germanic base *fleh- (see flax).

Another theory traces the Late Latin word to a metathesis of Latin vasculum. "The assumption that the word is of Teut[onic] origin is chronologically legitimate, and presents no difficulty exc[ept] the absence of any satisfactory etymology" [OED]. The similar words in Finnish and Slavic are held to be from Germanic.

Proto-Indo-European root meaning "to plait." It is an extended form of root *pel- (2) "to fold."

It forms all or part of: accomplice; application; apply; complex; complexion; complicate; complication; complicity; deploy; display; duplex; duplicate; duplicity; employ; explicate; explicit; exploit; flax; implex; implicate; implication; implicit; imply; multiply; perplex; perplexity; plait; plash (v.2) "to interlace;" pleat; -plex; plexus; pliable; pliant; plie; plight (n.1) "condition or state;" ply (v.1) "work with, use;" ply (v.2) "to bend; ply (n.) "a layer, fold;" replica; replicate; replication; reply; simplex; splay; triplicate.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit prasna- "turban;" Greek plekein "to plait, braid, wind, twine," plektos "twisted;" Latin plicare "to lay, fold, twist," plectere (past participle plexus) "to plait, braid, intertwine;" Old Church Slavonic plesti "to braid, plait, twist," Russian plesti; Gothic flahta "braid;" Old Norse fletta, Old High German flehtan "to plait;" Old English fleax "cloth made with flax, linen."

late 14c., "flax prepared for spinning," also "refuse of flax used as kindling," somehow from the source of Old English lin "flax" (see linen). Perhaps from or by influence of French linette "grain of flax," diminutive of lin "flax," from Latin linum "flax, linen;" Klein suggests from Latin linteum "linen cloth," neuter of adjective linteus.

Later "flocculent flax refuse used as tinder or for dressing wounds" (c. 1400). Still used for "flax" in Scotland in Burns' time. Applied to stray cotton fluff from 1610s, though in later use this is said to be American English.

small finch-like Eurasian songbird, 1530s, from French linette "grain of flax," diminutive of lin "flax," from Latin linum "flax, linen thread" (see linen). Flaxseed forms much of the bird's diet. Old English name for the bird, linetwige, with second element perhaps meaning "to pluck," yielded Middle English and dialectal lintwhite. Also compare German Hänfling "linnet," from Hanf "hemp."

Old English linsæd "seed of flax," from līn "flax" (see linen) + sæd "seed" (see seed (n.)). Used in ancient times as a source of medical treatments, in later use to produce linseed oil, used in paint, ink, varnishes, etc.

"cloth from woven flax," early 14c., noun use of adjective linen "made of flax" from Old English līn "flax, linen thread, linen cloth" + -en (2). Old English lin is from Proto-Germanic *linam (source also of Old Saxon, Old Norse, Old High German lin "flax, linen," German Leinen "linen," Gothic lein "linen cloth"), probably an early borrowing from Latin linum "flax, linen," which, along with Greek linon is from a non-Indo-European language. Beekes writes, "Original identity is possible, however, since the cultivation of flax in Central Europe is very old. Still, it is more probable that linon and linum derive from a Mediterranean word. The word is unknown in Indo-Iranian (but the concept is, of course)." Lithuanian linai, Old Church Slavonic linu, Irish lin probably are ultimately from Latin or Greek.

Woolen has begun the same evolution. Meaning "articles of linen fabric collectively" is from 1748, now sometimes extended unetymologically to cotton and artificial fabrics. The Old English noun also carried into Middle English as lin (n.) "linen" and persisted into 17c. and later in technical uses. The Middle English phrase under line (c. 1300) meant "in one's clothes." Linen-lifter (1650s) was old slang for an adulterous male.

"to apply a brake to a wheel," 1868, from brake (n.1). Earlier, "to beat flax" (late 14c.). Related: Braked; braking.