plan (n.)youdaoicibaDictYouDict[plan 词源字典]
1670s as a technical term in perspective drawing; 1706 as "drawing, sketch, or diagram of any object," from French plan "ground plan, map," literally "plane surface" (mid-16c.), from Latin planum "level or flat surface," noun use of adjective planus "level, flat" (see plane (n.1)). The notion is of "a drawing on a flat surface." Meaning "scheme of action, design" is first recorded 1706, possibly influenced by French planter "to plant," from Italian planta "ground plan."[plan etymology, plan origin, 英语词源]
plan (v.)youdaoicibaDictYouDict
1728, "make a plan of," from plan (n.). Related: Planned; planning; plans. Planned economy is attested from 1931. Planned Parenthood (1942) formerly was Birth Control Federation of America.
planar (adj.)youdaoicibaDictYouDict
1850, from Latin planaris "level, flat," from planum "plane" (see plane (n.1)).
Planaria (n.)youdaoicibaDictYouDict
flat worm-like animal, 1819, from Modern Latin (1776) noun use of fem. of Latin planarius, literally "on level ground" (here used to mean "flat"), from planum, planus "flat, level, even, plain" (see plane (n.1)). Related: Planarian.
planchet (n.)youdaoicibaDictYouDict
"metal disk out of which a coin is made," 1610s, from French planchette, literally "a small board," diminutive of Old French planche (12c.), from Latin planca "board, slab, plank" (see plank). The planchette used in automatism and on Ouija boards is a re-borrowing of the French word, 1860.
PlanckyoudaoicibaDictYouDict
in physics, in reference to the work of German physicist Max Planck (1858-1947); such as Planck's constant, attested in English from 1901.
plane (n.1)youdaoicibaDictYouDict
"flat surface," c. 1600, from Latin planum "flat surface, plane, level, plain," noun use of neuter of adjective planus "flat, level, even, plain, clear," from PIE *pla-no- (cognates: Lithuanian plonas "thin;" Celtic *lanon "plain;" perhaps also Greek pelanos "sacrificial cake, a mixture offered to the gods, offering (of meal, honey, and oil) poured or spread"), suffixed form of root *pele- (2) "to spread out; broad, flat" (cognates: Old Church Slavonic polje "flat land, field," Russian polyi "open;" Old English and Old High German feld, Middle Dutch veld "field"). Introduced (perhaps by influence of French plan in this sense) to differentiate the geometrical senses from plain, which in mid-16c. English also meant "geometric plane." Figurative sense is attested from 1850. As an adjective from 1660s.
plane (n.2)youdaoicibaDictYouDict
1908, short for aeroplane (see airplane).
plane (n.3)youdaoicibaDictYouDict
"tool for smoothing surfaces," mid-14c., from Old French plane, earlier plaine (14c.), from Late Latin plana, back-formation from planare "make level," from Latin planus "level, flat" (see plane (n.1)).
plane (v.2)youdaoicibaDictYouDict
"soar, glide on motionless wings," early 15c., from Old French planer "to hover (as a bird), to lie flat," from plan (n.) "plane," from Latin planum "flat surface" (see plane (n.1)), on notion of bird gliding with flattened wings. Of boats, etc., "to skim over the surface of water," it is first found 1913. Related: Planed; planing.
plane (n.4)youdaoicibaDictYouDict
"tree of the genus Platanus," late 14c., from Old French plane, earlier plasne (14c.), from Latin platanus, from Greek platanos, earlier platanistos "plane tree," a species from Asia Minor, associated with platys "broad" (see plaice (n.)), in reference to its leaves. Applied since 1778 in Scotland and northern England to the sycamore, whose leaves somewhat resemble those of the true plane tree.
plane (v.1)youdaoicibaDictYouDict
"to make smooth," early 14c., "to gloss over, explain away;" mid-14c. as "to make smooth or even," from Old French planer "to smooth, level off; wipe away, erase" (12c.), from Late Latin planare "make level," from Latin planus "level, flat" (see plane (n.1)). In early use in English often plain. Related: Planed; planing.
planet (n.)youdaoicibaDictYouDict
late Old English planete, from Old French planete (Modern French planète), from Late Latin planeta, from Greek planetes, from (asteres) planetai "wandering (stars)," from planasthai "to wander," of unknown origin, possibly from PIE *pele- (2) "flat, to spread" on notion of "spread out." So called because they have apparent motion, unlike the "fixed" stars. Originally including also the moon and sun; modern scientific sense of "world that orbits a star" is from 1630s.
planetarium (n.)youdaoicibaDictYouDict
1734, "orrery," Modern Latin, from Late Latin planeta (see planet) + Latin -arium "a place for." Sense of "device for projecting the night sky onto the interior of a dome" is attested from 1929.
planetary (adj.)youdaoicibaDictYouDict
1590s; see planet + -ary. Probably from Late Latin planetarius "pertaining to a planet or planets," but this is attested only as "an astrologer." Planetary nebula, so called for its shape, attested from 1785.
plangent (adj.)youdaoicibaDictYouDict
"beating with a loud sound," 1822, from Latin plangentem (nominative plangens), present participle of plangere "to strike, beat" (see plague (n.)). Related: Plangently.
plani-youdaoicibaDictYouDict
word-forming element meaning "level, plane," from Latin plani-, from planus "flat, level" (see plane (n.1)).
planisphere (n.)youdaoicibaDictYouDict
late 14c., from Medieval Latin planisphaerium, from Latin planus (see plane (n.1)) + sphaera (see sphere (n.)).
plank (n.)youdaoicibaDictYouDict
late 13c. (c. 1200 as a surname), from Old North French planke, variant of Old French planche "plank, slab, little wooden bridge" (12c.), from Late Latin planca "broad slab, board," probably from Latin plancus "flat, flat-footed," from PIE *plak- (1) "to be flat" (see placenta). Technically, timber sawed to measure 2 to 6 inches thick, 9 inches or more wide, and 8 feet or more long. Political sense of "item of a party platform" is U.S. coinage from 1848. To walk the plank, supposedly a pirate punishment, is first attested 1789 and most early references are to slave-traders disposing of excess human cargo in crossing the ocean.
planktology (n.)youdaoicibaDictYouDict
1892, from German planktologie (1891); see plankton + -logy. The native formation planktonology (1896) is less common.