Đồng nghĩa của on the sly

Đồng nghĩa: furtively,

secretly clandestinely discreetly privately slyly furtively sneakily confidentially covertly stealthily surreptitiously unofficially in private in secret on the quiet under cover on the side under the counter behind closed doors behind the scenes by stealth sub rosa quietly in camera in confidence in strict confidence underhandedly insidiously on the QT hush-hush in holes and corners conspiratorially unobserved without anyone knowing privily behind someone's back undercover obscurely under wraps underground under the table deceitfully wildcat intimately personally backstage behind your back without someone's knowledge in secrecy out of sight in hiding in petto between ourselves off the record under the rose between you, me, and the bedpost between you, me, and the gatepost à huis clos on the q.t. hushedly between us entre nous between you and me with no one else present huggermugger alone behind one's back confidingly sub-rosa circumspectly cautiously carefully closely well between themselves between yourselves very well between you and me and the gatepost between you and me and the bedpost between you and me and the doorpost between you and me and the wall off the cuff cunningly don't breathe a word in on the ground floor craftily foxily intelligently shrewdly shiftily

surreptitious clandestine covert furtive secret stealthy sly sneaking sneaky undercover underhand veiled backstair backstairs behind-the-scenes cloak-and-dagger concealed fraudulent hidden hole-and-corner hugger-mugger hush-hush private privy secretive sneak stealth unauthorised unauthorized underground underhanded black indirect skulking slinking sub-rosa under-the-table under the table under wraps on the QT closet shrouded confidential shifty unbowed back-alley wily cunning crafty devious shady cloaked artful tricky conspiratorial disguised guileful slippery duplicitous undisclosed oblique unrevealed masked scheming dishonest unscrupulous unethical foxy crooked unfair insidious designing covered deceitful treacherous calculating dirty two-faced evasive dishonourable under-the-counter sidelong camouflaged unofficial discreet unseen dishonorable clouded screened hole-in-the-corner subtle sideways enigmatic disreputable deceptive dubious conniving double-dealing snide cheating unknown buried Machiavellian obscured dodgy dark top-secret mystic incognito obscure deep quiet unexposed behind someone's back invisible on the quiet immoral unprincipled slick Janus-faced shonky silent feline catlike catty noiseless slim classified two-timing disingenuous illegal cautious top secret murky surprise enigmatical arcane strictly confidential unpublished esoteric intriguing untold indistinct indiscernible shrewd snidey dissembled mysterious occult low-down imperceivable inconspicuous abstruse sub rosa backdoor latent dirty-dealing eclipsed restricted undetected behind the scenes out of sight not for publication off the record not to be disclosed not for circulation not to be made public not visible in the dark out of view unreported on the side in secret mean subversive shorthanded intelligence contemptible slinky illicit illegitimate spy double-crossing unjust quick nefarious creep underneath bootleg unlawful side stinky lubricious mean-spirited undeclared unprofessed cloak and dagger elusive creepy circumspect unsuspected under the counter QT ulterior incog in holes and corners hole and corner not obvious withheld sheltered slanted snug tect cabalistic protected implied closed inside slanting not on view privileged clever hushed intimate backstage nonpublic unsporting unsportsmanlike offstage suppressed censored fly below the belt ambiguous strange unenlightened unintelligible out-of-the-way mystical non-public carny beguiling cute fishy bent cagey cagy cowardly yellow under one's hat tête-à-tête in camera not open close to one's chest one-on-one not in the public domain insincere in ambush inscrutable erring errant obliquitous gimmicky hinted at underlying ill-defined smooth vague unclear playing politics put on playing games reticent uncommunicated not straightforward faking one out unrecognizable shielded unrecognisable hooded roundabout perfidious sinister corrupt false wormlike perilous ensnaring backhanded dangerous snaky astute uncanny impenetrable cryptic nebulous opaque sphinxlike magical hidden away imperceptible mum unseeable unnoticeable mom non-committal unnoticed undetectable indistinguishable unobserved with a lid on unobtrusive sphinx-like like a snake in the grass nonexistent unperceivable shadowy inappreciable unapparent intangible unobservable ghostly insensible perdu impalpable ethereal vaporous imaginary unviewable imponderable gaseous not in view not in sight impossible to detect

on the small side on the spectrum on the spot on-the-spot on the spur of the moment on the square on the slate on the slant on the skids on the skew on the side of on the sidelines