obrepto

āvi, 1
I. v. freq. n. [id.], to steal on unawares, to come on imperceptibly (very rare): ne quis obreptaverit, Plaut. Pers. 1, 2, 27: obreptantibus Satyris, Plin. 35, 10, 36, § 109 (but in Cic. Att. 6, 5, 3, the correct read. is obrepebat).
Lewis & Short
A Latin Dictionary, 1879
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