英语词源字典 - 在线词源网站

underbred (adj.)[underbred 词源字典]: "of inferior breeding, vulgar," 1640s, from under + past participle of breed (v.). Of animals, "not pure bred," attested from 1890.[underbred etymology, underbred origin, 英语词源]
underbrush (n.): "shrub and small trees in a forest," 1775, from under + brush (n.2). Originally American English; compare undergrowth, attested in the same sense from 1600.
undercarriage (n.): 1794, from under + carriage (n.). Meaning "landing gear of an aircraft" is recorded from 1911.
undercharge (v.): 1630s, from under + charge (v.).
underclass (n.): "subordinate social class," 1894, from under (adj.) + class (n.). A loan-translation of Swedish underklass.
underclassman (n.): "sophomore or freshman," 1869, American English, from under (adj.) + class (n.) in the school form sense + man (n.).
undercover (adj.): 1854, "sheltered," from under + cover (n.). Sense of "operating secretly" attested from 1920.
undercroft (n.): "crypt of a church; underground vault," late 14c., from under + croft.
undercurrent (n.): 1660s, "stream of water or air flowing beneath the surface or beneath another current," a hybrid formed from under + current (n.). The figurative sense of "suppressed or underlying character" is attested from 1817.
undercut (v.): late 14c., "to cut down or off," from under + cut (v.). In the commercial sense of "sell at lower prices" (or work at lower wages) it is first attested 1884. Figurative sense of "render unstable, undermine" is recorded from 1955, from earlier literal meaning "cut so as to leave the upper portion larger than the lower" (1874).
underdeveloped (adj.): 1892, in photography, from under + past participle of develop (v.). In reference to countries or regions, recorded from 1949.
underdog (n.): "the beaten dog in a fight," 1887, from under + dog (n.). Compare top dog "dominant person in a situation or hierarchy" (see top (adj.)).
I'm a poor underdog
But tonight I will bark
With the great Overdog
That romps through the dark.

[from "Canis Major," Robert Frost, 1928]
underdone (adj.): 1680s, in reference to cooked meat, from under + done. Old English underdon (v.), Middle English underdo meant "to put under, to subject, subjugate."
underdressed (adj.): also under-dressed, "too plainly dressed," 1759, from under (adv.) + past participle of dress (v.).
underestimate (v.): 1812, "to estimate at too low an amount," from under + estimate (v.). Meaning "to rank too low, undervalue" is recorded from 1850. Related: Underestimated; underestimating.
underexposed (adj.): 1861, in photography, from under + past participle of expose (v.).
underfeed (v.): 1650s, from under + feed (v.). Related: Underfed; underfeeding.
underfoot (adv.): c. 1200, underfot "under the feet," from under + foot (n.). Compare similarly formed Middle Dutch ondervoete. As an adjective, attested from 1590s; in reference to persons, "continually in the way," it is recorded from 1891. Middle English under fot meant "vanquished, overcome."
undergarment (n.): 1520s, from under + garment (n.).
undergird (v.): 1520s, from under + gird (v.). Related: Undergirded; undergirding.