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alterno, āvi, ātum, 1, v. a. and n. [alternus]: aliquid, to do one thing and then another, to do a thing by turns, to interchange with something, to alternate (first in the poets of the Aug. per., later most freq. in Pliny): alternare vices, Ov. M. 15, 409: alternant spesque timorque fidem, make it at one time credible, at another not, id. H. 6, 38: hirundines in fetu summā aequitate alternant cibum, i. e. give to the young their food in succession, Plin. 10, 33, 49, § 92; so id. 15, 3, 3, § 12; 29, 4, 20, § 68; Col. 5, 6, 4; Sil. 1, 554; 9, 354; 11, 60; * Suet. Ner. 1.
Without an obj.: haec alternanti potior sententia visa est, hesitating, Verg. A. 4, 287: alternantes proelia miscent, fight by turns, id. G. 3, 220: arborum fertilitas omnium fere alternat, alternates, i. e. they bear every other year, Plin. 16, 6, 7, § 18; so id. 31, 3, 23, § 40; 37, 10, 60, § 167.
With cum: cum symphoniā alternāsse, Plin. 10, 29, 43, § 84.