obtained, done, made, etc., by stealth; secret or unauthorized; clandestine: a surreptitious glance.
2.
acting in a stealthy way.
3.
obtained by subreption; subreptitious.
Origin: 1400–50;late Middle English < Latinsurreptīcius stolen, clandestine, equivalent to surrept(us), past participle of surripere to steal, (sur-sur-2 + rep-, combining form of rapere to snatch, rape1 + -tus past participle suffix) + -īcius-itious
mid-15c., from L. surrepticius "stolen, furtive, clandestine," from surreptus, pp. of surripere "seize secretly," from sub "from under" (hence, "secretly") + rapere "to snatch" (see rapid). Related: Surreptitiously.