Ditzo noun
A forgetful person; a fool
I am such a ditzo because I often forget my key.
What a ditzo! She forgot her wallet again.
He is a ditzo. He cannot tell duck eggs from chicken eggs.
If you say someone goes in one ear and out the other, you mean they don't pay attention to and forget about what you have just said immediately.
(n): a fool person,
(adj): stupid, foolish, silly
A blustering idiot
Not intelligent, dumb or foolish
This word took its root from the adjective "ditzy", which was first recorded in 1973.
If you fall for someone's trick the first time then they are at fault.
Are you going to mess with me again? Fool me once, shame on you; fool me twice, shame on me.