Synonyms for Gullible (same or very similar meaning)
WordNet sense 1 (naive and easily deceived or tricked):
green, fleeceable
WordNet sense 2 (marked by or showing unaffected simplicity and lack of guile or worldly experience):
naif, naive
WordNet sense 3 (not alert to danger or deception):
unwary
From the ODE community, based on WordNet
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