c. 1200, flour, also flur, flor, floer, floyer, flowre, "the blossom of a plant; a flowering plant," from Old French flor "flower, blossom; heyday, prime; fine flour; elite; innocence, virginity" (12c., Modern French fleur), from Latin florem (nominative flos) "flower" (source of Italian fiore, Spanish flor), from PIE root *bhel- (3) "to thrive, bloom."
From late 14c. in English as "blossoming time," also, figuratively, "prime of life, height of one's glory or prosperity, state of anything that may be likened to the flowering state of a plant." As "the best, the most excellent; the best of its class or kind; embodiment of an ideal," early 13c. (of persons, mid-13c. of things); for example flour of milk "cream" (early 14c.); especially "wheat meal after bran and other coarse elements have been removed, the best part of wheat" (mid-13c.). Modern spelling and full differentiation from flour (n.) is from late 14c.
In the "blossom of a plant" sense it ousted its Old English cognate blostm (see blossom (n.)). Also used from Middle English as a symbol of transitoriness (early 14c.); "a beautiful woman" (c. 1300); "virginity" (early 14c.). Flower-box is from 1818. Flower-arrangement is from 1873. Flower child "gentle hippie" is from 1967.
It forms all or part of: blade; bleed; bless; blood; blow (v.2) "to bloom, blossom;" bloom (n.1) "blossom of a plant;" bloom (n.2) "rough mass of wrought iron;" blossom; cauliflower; chervil; cinquefoil; deflower; defoliation; effloresce; exfoliate; feuilleton; flora; floral; floret; florid; florin; florist; flour; flourish; flower; foil (n.) "very thin sheet of metal;" foliage; folio; folium; gillyflower; Phyllis; phyllo-; portfolio; trefoil.
It is the hypothetical source of/evidence for its existence is provided by: Greek phyllon "leaf;" Latin flos "flower," folio, folium "leaf;" Middle Irish blath, Welsh blawd "blossom, flower;" Gaelic bile "leaflet, blossom;" Old English blowan "to flower, bloom."
1570s, common name of Dianthus, a garden plant of various colors; a word of unknown origin. It is perhaps from pink (v.) via the notion of "perforated" (scalloped) petals. Or perhaps it is from Dutch pink "small, narrow" (see pinkie), itself obscure, via the term pinck oogen "half-closed eyes," literally "small eyes," which was borrowed into English (1570s) and may have been used as a name for Dianthus, which sometimes has small dots resembling eyes.
The noun meaning "pale red color, red color of low chroma but high luminosity" is recorded by 1733 (pink-coloured is recorded from 1680s), from one of the common colors of the flowers. The adjective pink is attested by 1720. As an earlier name for such a color English had incarnation "flesh-color" (mid-14c.), and as an adjective incarnate (1530s), from Latin words for "flesh" (see incarnation) but these also had other associations and tended to drift in sense from "flesh-color, blush-color" toward "crimson, blood color."
The flower meaning led (by 1590s) to a figurative use for "the flower" or highest type or example of excellence of anything (as in Mercutio's "Nay, I am the very pinck of curtesie," Rom. & Jul. II.iv.61). Compare flour (n.). The political noun sense "person perceived as left of center but not entirely radical (i.e. red)" is attested by 1927, but the image dates to at least 1837. Pink slip "discharge notice" is attested by 1915; pink slips had various connotations in employment in the first decade of the 20th century, including a paper signed by a worker to testify he would leave the labor union or else be fired. To see pink elephants "hallucinate from alcoholism" is from 1913 in Jack London's "John Barleycorn."
1707, "dust, powdery substance," from Latin farina "ground wheat, flour, meal," from far (genitive farris) "husked wheat, emmer; grain, flour," from Proto-Italic *fars "flour," from PIE *bhars-, with cognates in Old Irish bairgen "bread, loaf," Welsh bara "bread," Serbo-Croatian brašno "flour, food," Latvian bariba "food," Gothic barizeins "from barley," Old Norse barr "grain," Old English bere "barley;" according to de Vaan perhaps a loan-word from a non-IE language.
meal from the large, hard kernels of wheat left after the fine flour has been sifted, 1797, alteration of Italian semolino "grits; paste for soups," diminutive of semola "bran," from Latin simila "the finest flour," probably from the same Semitic source as Greek semidalis "the finest flour" (compare Assyrian samidu, Syrian semida "fine meal").