- surreptitious (adj.)
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- mid-15c., from Latin surrepticius "stolen, furtive, clandestine," from surreptus, past participle of surripere "seize secretly, take away, steal, plagiarize," from assimilated form of sub "from under" (hence, "secretly;" see sub-) + rapere "to snatch" (see rapid). Related: Surreptitiously.