off guard

from WordNet (r) 3.0 (2006)

off guard
    adj 1: not prepared or vigilant; "the blow caught him napping";
           "caught in an off-guard moment"; "found him off his
           guard" [syn: {napping}, {off-guard(a)}, {off guard(p)},
           {off one's guard(p)}, {off his guard}, {off her guard},
           {off your guard}]

from Moby Thesaurus II by Grady Ward, 1.0

38 Moby Thesaurus words for "off guard":
      asleep, culpably negligent, derelict, goofing off, inadvertent,
      inattentive, incautious, laissez-faire, lax, loose, napping,
      neglectful, neglecting, negligent, nodding, noninterfering,
      nonrestrictive, overly permissive, permissive, procrastinating,
      relaxed, remiss, scamping, skimping, slack, sleeping, slighting,
      slurring, unalert, uncautious, uncircumspect, unguarded,
      unprepared, unready, unrigorous, unvigilant, unwary, unwatchful

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