c. 1400, from horse (n.) + tail (n.). As a kind of plant, from 1530s.

substance prepared from fruit of the vanilla plant, 1859, from vanilla + -in (2).

plant native to Mexico and the southern U.S., by 1831, in a California context, from Mexican Spanish amole, name for various plant-roots used as detergents, from Nahuatl (Aztecan) amolli "soap-root."

"intentionally dwarfed potted tree," 1914, from Japanese, from bon "basin, pot" + sai "to plant."

"formed of living plants," 1530s, from earlier noun, "a living plant set to grow for a hedge" (late 15c.), from quick (n.) "a live fence or hedge formed of some growing plant," especially hawthorn (mid-15c.); see quick (adj.) + set (v.).

"seed-capsule of a plant native to southern India and Ceylon," used in medicine and cookery, 1550s, from French cardamome, from Latin cardamomum, from Greek kardamomon, from kardamon "cress" (which is of unknown origin) + amomon "spice plant." The word was in English from late 14c. in Latin form.

modern plant genus, 1771, Latin, taken by botanists from Greek Silphion, the name of a North African Mediterranean plant whose identity has been lost, the gum or juice of which was prized by the ancients as a condiment and a medicine. Probably the word is ultimately of African origin.

composite flowering plant of North America noted for the common allergic reaction to its pollen, 1790, from ragged + weed (n.); so called from shape of the leaves. The name had been applied to a different plant (ragwort) from 1650s.

"plant-eating animal," 1851, from Modern Latin Herbivora (1830) or French herbivore (1748), from neuter plural of Latin herbivorus, from herba "a plant" (see herb) + vorare "devour, swallow" (from PIE root *gwora- "food, devouring").

"loud warning horn," 1908, originally on automobiles, said to have been named for the company that sold them (The Klaxon Company; distributor for Lovell-McConnell Manufacturing Co., Newark, New Jersey), but probably the company was named for the horn, from a made-up word likely based on Greek klazein "to roar," which is cognate with Latin clangere "to resound" (compare clang).