Synonyms and related words :
broad-minded, culpably negligent, derelict, freethinking, inadvertent, inattentive, laissez-faire, latitudinarian, lax, liberal, libertarian, libertine, loose, neglectful, neglecting, negligent, noninterfering, off-guard, open-minded, overly permissive, permissive, procrastinating, relaxed, remiss, scamping, skimping, slack, slighting, slurring, tolerant, unbigoted, uncircumspect, unguarded, unrigorous, unwary, unwatchful