O / obreptĭo
noun

obreptĭo

gen. obreptōnis · gender feminine · decl. 3rd
a creeping; stealing on, a coming on suddenly; by surprise, a surprise by extension
a creeping or stealing on, a coming on suddenly or by surprise, a surprise (post - Aug.): Ventidius, aggressus per obreptionem, Front. Strat. 2, 5, 36; Arn. 5, 162: arrogari per obreptionem, Dig. 2, 4, 10: precum, Cod. Th. 5, 8, 1. —Transf. (eccl. Lat.), a surprise by sudden temptation, Ambros. in Luc. 10, § 72.