Definition of "surreptitious"

He read the letter aloud. Sophia listened with the studied air of one for whom, even in these days, a title possessed some surreptitious allurement.

1922, Ben Travers, chapter 1, in A Cuckoo in the Nest‎

It is also worth noting the case law on prisoners' correspondence which establishes that interception of a person's communications need not be surreptitious in order to amount to an interference with respect to Art 8 (1) [ECHR].

1998, Lee A. Bygrave, “Data Protection Pursuant to the Right to Privavy in Human Rights Treaties”, in International Journal of Law and Information Technology, volume 6, number 3, pages 260–261