Question

what is the Antonym of gullible

Answer 1

suspicious or cynical

Definition of antonyms :: An antonyms are that word which means the opposite of an anthor word.

For example
Sad:: happy
cold:: hot
rich:: poor
exterior :: interior
true :: false

Answer 2

hey dear your answer is here:-

cynical or suspicious is the antonomy of gullible.

hope it helps