Surreption

n. [ L. surreptio, or subreptio. Cf. Subreption. ] 1. The act or process of getting in a surreptitious manner, or by craft or stealth. [ 1913 Webster ]

Fame by surreption got
May stead us for the time, but lasteth not. B. Jonson. [ 1913 Webster ]

2. A coming unperceived or suddenly. [ 1913 Webster ]