c. 1300, romaunce, "a story, written or recited, in verse, telling of the adventures of a knight, hero, etc.," often one designed principally for entertainment, from Old French romanz "verse narrative" (Modern French roman), also "the vulgar language," originally an adverb, "in the vernacular language," from Vulgar Latin *romanice scribere "to write in a Romance language" (one developed from Latin instead of Frankish), from Latin Romanicus "of or in the Roman style," from Romanus "Roman" (see Roman).
The sense evolution is because medieval vernacular tales (as opposed to Latin texts) usually told chivalric adventures full of marvelous incidents and heroic deeds. "The spelling with -aunce, -ance was very early adopted in English, probably on the analogy of abstract sbs." [OED].
In reference to literary works, in Middle English often meaning ones written in French but also applied to native compositions. The literary sense was extended by 1660s to "a love story, the class of literature consisting of love stories and romantic fiction." Meaning "imaginative, adventurous quality" first recorded 1801; that of "love affair" is from 1916. Romance novel is attested by 1820. Compare Romance (adj.).
late 14c., romauncen, "recite a narrative poem," from romance (n.) and also from Old French romancier "narrate in French; translate into French," from romanz (n.). Later "invent fictitious stories" (1670s), then "be romantically enthusiastic" (1849); meaning "court as a lover" is from 1938, probably from romance (n.). Related: Romanced; romancing.
mid-14c., "French; in the vernacular language of France" (contrasted to Latin), from Old French romanz "French; vernacular," from Late Latin Romanice, from Latin Romanicus (see Roman). Extended 1610s to other modern tongues in the south and west of Europe derived from Latin (Spanish, Italian, etc.); thus, collectively, "pertaining to the modern languages which arose out of the Latin of the provinces of Rome." Compare romance (n.).
mid-14c., "chronicler writing in French," from Anglo-French romancour, Old French romanceour, from romanz (see romance (n.)). From 1660s as "one who writes extravagant fictions;" later, "one inclined to romantic imagination" (the main 19c. sense); modern use for "seducer, wooer having a romantic quality" appears to be a new formation c. 1967 from romance (v.).
"Rhaeto-Romanic," the Latin-derived language spoken in the Grisons region of eastern Switzerland, 1660s, from Grisons Rumansch, from Late Latin Romanice "in Vulgar Latin" (see romance (n.)).
1715, "descended from Latin" (compare romance (n.)), later "architectural style in Western Europe between the Roman and Gothic periods" (1819), from Roman + -esque. Influenced by French romanesque, from Late Latin Romanice "in Vulgar Latin." As a noun, "the early medieval style in architecture," by 1830.
"a novel," 1765, from French roman, from Old French romanz (see romance (n.)). Roman à clef, novel in which characters represent real persons, literally "novel with a key" (French), is attested in English by 1893. And, in the days when a tec was popular reading, roman policier "a story of police detection" (1928).
1910, from German Bildungsroman, from Bildung "education, formation, growth" (from Bild "picture, image, figure") + roman "novel" (see romance (n.)). A novel set in the formative years, or the time of spiritual education, of the main character. German Bild is from Old High German bilade, from Proto-Germanic *biliþja or *bilaþja, the source also of Dutch beeld, Old English biliþe, but the ultimate origin is unknown.
1650s, "of the nature of a literary romance, partaking of the heroic or marvelous," from French romantique "pertaining to romance," from romant "a romance," an oblique case or variant of Old French romanz "verse narrative" (see romance (n.)).
Of places, "characterized by poetic or inspiring scenery," by 1705. As a literary style, opposed to classical (q.v.) since before 1812; it was used of schools of poetry in Germany (late 18c.) and later France. In music, "characterized by expression of feeling more than formal methods of composition," from 1885. Meaning "characteristic of an ideal love affair" (such as usually formed the subject of literary romances) is from 1660s. Meaning "having a love affair as a theme" is from 1960. Related: Romantical (1670s); romantically; romanticality. Compare romanticism.