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spontānĕus, a, um, adj. [sponte], of one’s free will, voluntary, spontaneous (late Lat.): mors, Macr. Somn. Scip. 2, 22: voluntas, free will, Cod. Just. 2, 3, 2: benignitates numinum, Arn. 3, p. 114.
Adv.: spontānĕē, voluntarily, willingly, of one’s own mind: apparere tumores, Theod. Prisc. 1, 8; Vulg. 1 Pet. 5, 2; Hier. Ep. 52, n. 7.