The Collaborative International Dictionary
Obreptitious
Obreptitious \Ob`rep*ti"tious\, a. [L. obreptitus. See
Obreption.]
Done or obtained by surprise; with secrecy, or by concealment
of the truth. [R.]
--Cotgrave.
Wiktionary
obreptitious
a. Done or obtained by surprise, with secrecy, or by concealment of the truth.