Did you know that the word "gullible" is not in the dictionary?

Perhaps you were trying to find if we were gullible. Anyway in my dictionary it is defined as 'easily deceived'. It is a derivative of the word 'gull' meaning a dupe : an easily duped person, a cheat, to beguile or hoax. Look under gull (not the bird, that's a different definition) and you will find it, that is if your dictionary is any good.