释义 |
obvert, v.|əbˈvɜːt| [ad. L. obvert-ĕre to turn towards or against, f. ob- (ob- 1 a, b) + vertĕre to turn.] †1. trans. To turn (something) towards; to place fronting. Obs.
1623Cockeram, Obuert, to turne against one. 1646Sir T. Browne Pseud. Ep. vi. vii. 309 The rooms of cænation in the Summer, he obverts unto the Winter ascent, that is, South-East. 1686Goad Celest. Bodies i. xv. 95 The Lunar Light being obverted towards us..in the Quadrates. 1781Wesley Wks. (1872) IV. 211 If the northern hemisphere be obverted to the sun longer than the southern. †2. To turn (a thing) in a contrary direction.
1646Sir T. Browne Pseud. Ep. 60 If wee place a Needle touched at the foote of tongues or andirons, it will obvert or turne aside its lyllie or North point, and conforme its cuspis or South extreme unto the andiron. 1657Tomlinson Renou's Disp. 131 That the manner of preparation and mixtion be not obverted thereby. 3. Logic. To change the quality of (a proposition) in the way of obversion.
1870A. Bain Logic i. 110 Obvert the predicate, and prefix the sign of negation. 1896J. Welton Man. Logic (ed. 2) I. iii. iii. 251 The one simple rule for obverting any proposition:—Negative the predicate and change the quality, but leave the quantity unaltered. Hence obˈverted ppl. a.
1664Evelyn Sylva (1679) 20 Place to warm south, or the obverted pole. 1870A. Bain Logic i. 115 These obverted forms are Particular Affirmatives, and are therefore converted simply. 1896J. Welton Man. Logic (ed. 2) I. iii. iii. 249 The corresponding forms with negative predicates are termed the Obverted Converse, the Obverted Contrapositive, and the Obverted Inverse. |