Forms: 4 tropik, 6 -ycque(-we), -yk(e, 6–7 -ike, -ique, -icke, 6–8 -ick, 7– tropic. [ad. L. tropicus, a. Gr. τροπικός pertaining to the ‘turning’ of the sun at the solstice, tropical (hence as sb. [sc. κύκλος circle] the tropic); also, of the nature of a trope, figurative, f. τροπή turning. Cf. F. tropique (16th c.).] A. sb.
I. 1. Astr. † a. Each of the two solstitial points, the most northerly and southerly points of the ecliptic, at which the sun reaches his greatest distance north or south of the equator, and ‘turns’ or begins to move towards it again; also (loosely), each of the two signs (Cancer and Capricorn) at the beginning of which these points occur. Obs.
In quot. 1662 erroneously extended to include the equinoctial points.
c. 1391. Chaucer, Astrol., I. § 17. This signe of cancre is cleped the tropik of Somer, of tropos, þat is to seyn Agaynward, for thanne by-gynneth the sonne to passe fro vs-ward.
1579. E. K., Gloss. Spenser’s Sheph. Cal., Nov., 15. The sonne draweth low … toward his Tropick or returne.
1615. G. Sandys, Trav., 98. The Sunne performing his course in the winter Tropick.
1662. Stanley, Hist. Chaldaic Philos. (1701), 17/2. In Aries is the Spring Tropick, in Capricorn the Winter, in Cancer the Summer, in Libra the Autumnal.
b. Each of two circles of the celestial sphere (tropic of CANCER and tropic of CAPRICORN), parallel to the equinoctial or celestial equator, and distant about 23° 28′ north and south of it, touching the ecliptic at the solstitial points.
1503. Kalender of Sheph., i ij. The other two [circles] ar namyt tropycqwes, the oon of sommer the other of wynter.
1555. Eden, Decades, 183. The soonne … remaynynge continually betwene the two tropykes of Cancer and Capricorne. Ibid. (1561), trans. Cortez’ Arte Nauig., I. xv. 16. The Estiuall or sommer Tropyke.
1607. Topsell, Four-f. Beasts (1658), 112. Other by the Dogs, do understand the two Tropicks, which are (as it were) the two porters of the Sun for the South and North.
1625. N. Carpenter, Geog. Del., I. vi. (1635), 144. The Tropicks are Parallels bounding the Suns greatest declination.
1658. Waller, On Cromwell’s Death, 21. Under the Tropick is our Language spoke.
1837. Whewell, Hist. Induct. Sc. (1857), I. 114. Where the sun’s path touches the tropics.
1868. Lockyer, Elem. Astron., iii. (1879), 65. At 231/2° on either side of the equator are the Tropics.
c. fig. Turning-point; limit, boundary. (In quot. 1635 otherwise used: cf. 2 c.)
1635. Quarles, Embl., III. vii. (1718), 155. Our equinoctial hearts can never lie Secure, beneath the tropicks of that eye.
a. 1639. Wotton, Charac. Kings Eng., in Reliq. (1651), 166. States have their Conversions and Periods as well as Naturall Bodies, and we were come to our Tropique.
1670. Eachard, Cont. Clergy, 54. It was a zodiacal mercy!… for Christ keeps within the tropicks; He goes not out of the pale of the church.
1844. N. Paterson, Manse Garden, 63. Let rest and fatigue be your tropics and you will travel with unabated vigour over the undulating line of your ecliptic.
2. Geog. Each of two parallels of latitude on the earth’s surface (corresponding to the celestial circles, 1 b, and called likewise tropic of Cancer and tropic of Capricorn), distant about 23° 28′ north and south of the equator, being the boundaries of the torrid zone.
1527. R. Thorne, in Hakluyt, Voy. (1589), 252. From the Tropickes to both the Poles.
1604. E. G[rimstone], D’Acosta’s Hist. Indies, II. iv. 87. In Regions which lie without the Tropicks.
c. 1645. Howell, Lett. (1688), III. 409. Our late Navigators … who use to cross the Equator and Tropiques so often.
1711. Addison, Spect., No. 170, ¶ 13. It is a Misfortune for a Woman to be born between the Tropicks.
a. 1780. Watson, Philip III. (1839), 175. Countries … on this side of the northern tropic.
1878. Huxley, Physiogr., xx. 356. The boundaries of these zones are called tropics.
b. pl. With def. art.: The region between (and about) these parallels; the torrid zone and parts immediately adjacent.
1837. W. Irving, Capt. Bonneville, III. 145. The Mississippi; whose rapid current traverses a succession of latitudes … in a few days … almost from the frozen regions to the tropics.
1854. Emerson, Lett. & Soc. Aims, Resources, Wks. (Bohn), III. 203. The tropics are one vast garden.
1880. Haughton, Phys. Geog., iii. 130. The warm waters of the tropics are carried, bodily, into the temperate zone.
Comb. 1887. Daily News, 7 Nov., 3/1. That pulmonary disease … generally … fatal to the tropic-born anthropoids.
c. fig. in allusion to the excessive heat or luxuriant growth of the tropics.
1641. J. Jackson, True Evang. T., I. 138. The sixt Persecution … did so scorch within the Tropicks of the Church, that many thousands suffered.
1893. N. Y. New-Church Messenger, 19 April, 244. Mastodon-affections … swarming through the tropics of his soul.
II. † 3. pl. [tr. L. tropicī (Athanasius, etc.).] Name for a sect who interpreted Scripture, or certain passages of Scripture, metaphorically. (Cf. TROPIST.) Obs.
1585–7. T. Rogers, 39 Art., v. (1633), 23. Some affirme the holy Ghost to be but a meere creature, as did Arius,… the Tropickes, [etc.].
† 4. pl. Tropical or metaphorical uses of words; tropes. Obs.
1697. trans. Burgersdicius his Logic, I. xxvi. 104. The Change of the Word, from its proper Signification, as in the Tropicks.
B. adj.
I. 1. Astr. Connected with the sun’s ‘turning back’ towards the equator at the solstices; pertaining to the tropics, or to either tropic (in sense A. 1 a or b): = TROPICAL 1. Tropic circle or line = A. 1 b; tropic point = A. 1 a. Now rare or Obs.
1551. Recorde, Cast. Knowl. (1556), 24. These other two cyrcles … are called the twoo Tropike cyrcles after the greeke deriuation.
1616. Marlowe’s Faust., vi. Wks. (Rtldg.), 117/2. He views the clouds, the planets, and the stars, The tropic Zones.
1667. Milton, P. L., X. 675. Som say the Sun Was bid turn Reines from th’ Equinoctial Rode … Up to the Tropic Crab.
1667. Dryden, Sir Martin Mar-all, V. i. I have seen your hurricanos and your calentures, and your ecliptics and your tropic lines.
1701. Stanley’s Hist. Philos., Biog. b j. Stanley … thinks his Gnomon did only note the Tropick and Equinoctial Points.
† b. fig. or allusively. Of or pertaining to turning (in quot., in allusion to Jas. i. 17). Obs.
1677. Gale, Crt. Gentiles, II. IV. 258. It casts various shadows and causeth varietie of Seasons,… such is the ἀποσκίασμα or tropic shadow of the sun. But now the immutable God admits no such tropic shadows or variations.
2. Geog. Belonging to the tropics (in sense A. 2 or 2 b): = TROPICAL 2.
1799. Wordsw., Ruth, vii. No dolphin ever was so gay Upon the tropic sea.
1806. Maurice, Fall of Mogul, II. iv. 53. Relentless as the tropic whirlwind’s rage.
1855. Kingsley, Westw. Ho! xxv. The rapid tropic vegetation has reclaimed its old domains.
1875. Bennett & Dyer, trans. Sachs’ Bot., 832. The vital conditions of all plants growing at a great elevation and in Arctic countries must be different from those growing in the lowlands of the Tropic and Temperate zones.
b. fig. = TROPICAL 2 c.
[1852. Wordsw., Sonn., ‘We had a female Passenger,’ 10. Yet still her [a negro’s] eyes retained their tropic fire.]
1887. Daily News, 29 June, 5/2. Spring completely lost its way … and it was winter,… till this tropic time came upon us unawares.
3. a. Tropic bird, any bird of the family Phaethontidæ, comprising sea-birds resembling terns, widely found in tropical regions, and characterized by webbed feet, rapid flight, and varied coloration.
1681. Grew, Musæum, I. IV. iii. 74. The Tropick Bird. So called because said never to be seen but between the Tropicks.
1756. P. Browne, Jamaica, 482. The Tropic Bird … breeds on the most desolate rocks and lonely places and is seldom seen near any inhabited shores.
1825. Waterton, Wand. S. Amer., II. (1903), 64. Sometimes … the tropic bird comes near enough to let you have a fair view of the long feathers in his tail.
1896. Newton, Dict. Birds, 990. The Yellow-billed Tropic-bird, P[haethon] flavirostris. Ibid., 991. The Red-tailed Tropic-bird, P. rubricauda or phœnicurus.
b. Tropic crow: see quot.
1781. Latham, Synopsis Birds, I. I. 384. Tropic [1800 Shaw, Tropical] Crow. Length twelve inches and a half … From O-wy-hee … in the South Seas.
c. Tropic grape, the gulf-weed: = SEA-GRAPE 6.
1850. Miss Pratt, Comm. Things Sea-side, ii. 111. The Sea-grape is an olive-green weed, with long slender leaves, and berries about as large as a pea, from which it derived its name of Tropic Grape.
1852. Th. Ross, trans. Humboldt’s Trav., I. iii. 129. To the north of the Cape Verd Islands we met with great masses of floating seaweeds. They were the tropic grape (Fucus natans), which grows … only from the equator to the fortieth degree of north and south latitude.
II. 4. Biol. [Properly the second element of GEOTROPIC, HELIOTROPIC, etc., used as an inclusive or generic term (cf. TROPISM).] Pertaining to, consisting in, or exhibiting tropism.
1903. T. H. Morgan, Evol. & Adapt., xi. 399. Another instinct, that appears to be due to a tropic response, is the definite time of day at which some marine animals deposit their eggs.
