Synonyms of surreptitious

1 Syllable

sly, qt

2 Syllables

backstairs, hidden, veiled, sneaking, sneakier, stealthy, stealthier, devious, stealthiest, hush-hush, covert, sneaky, cloaked, skulking, slinking, sneakiest

3 Syllables

sub-rosa, lubricious, insidious, furtive, fraudulent, private, underhand

4 Syllables

cloak-and-dagger, hole-and-corner, undercover, dirty-dealing, clandestine

5 Syllables

under-the-table, unauthorized