1) Credulous 2) Deceivable 3) Fleeceable 4) Green 5) Naif 6) Naive 7) Susceptible 8) Unsuspecting 9) Unwary 10) Vulnerable 1) Credulous 2) Easily deceived or cheated 3) Easily duped 4) Easily fooled 5) Easily taken in 6) Easily tricked 7) Easily-duped 8) Fleeceable 9) Green 10) Innocent 11) Naif 12) Naive 13) Naive and easily deceived 14) Too trusting 15) Trusting 16) Uncritical 17) Unquestioning 18) Unsuspecting 
• (a.) Easily gulled; that may be duped.
Gul'li·ble adjective Easily gulled; that may be duped. -- 
easily gulled 
[adj] - easily tricked because of being too trusting
adjective easily tricked because of being too trusting; `gullible tourists taken in by the shell game`
easily deceived or cheated.
naive and easily deceived or tricked naive and easily deceived or tricked