Is snuck a word? Ask Conan O'Brien. It is a word and so Jennifer Garner found out. In an interview, Conan used the past participle of seek which is snuck. Garner rudely corrected Conan O'Brien in this video.
He did what I would have done: he got out the dictionary. She was really rude and out of place, but puckered up her lips and snuck off stage as soon as possible after O'Brien rudely laughed in her pretty snookered face! Go Conan!