Idiot means a stupid moron with no life. But it also means peculiar.
An idiot (scientific name: Idioticus stupidicus) is a stupid person, need I say more?
Idiot: ThE EaRtH Is FlAt!!!!!!!!!!!!
Any normal person: *facepalms*
A person who acts without little thought or care.
I may be an idiot, but indeed I am no fool.