Synonyms and related words :
artless, asleep, bluff, blunt, born yesterday, brash, brazen, brazenfaced, candid, careless, childlike, confiding, culpably negligent, derelict, direct, foolhardy, frank, goofing off, guileless, hasty, heedless, hotheaded, hubristic, ill-advised, improvident, imprudent, impudent, inadvertent, inattentive, incautious, inconsiderate, indiscreet, ingenu, ingenuous, injudicious, innocent, insolent, laissez-faire, lax, loose, mindless, naive, napping, neglectful, neglecting, negligent, nodding, noninterfering, nonrestrictive, off-guard, open, openhearted, outspoken, overbold, overcareless, overconfident, overly permissive, oversure, overweening, permissive, plain, procrastinating, rash, reckless, relaxed, remiss, scamping, simple, simplehearted, simpleminded, sincere, single-hearted, single-minded, skimping, slack, sleeping, slighting, slurring, temerarious, thoughtless, trustful, trusting, unadvised, unalert, uncautious, unchary, uncircumspect, unguarded, unprepared, unready, unreserved, unrigorous, unsophisticated, unthinking, unvigilant, unwatchful, unwise