knucklehead
Pronunciation:
/ˈnʌkl̩ˌhɛd/noun
Definitions
An idiot; a stupid or inept person
Example: Don't stick that screwdriver into the live electrical outlet, you knucklehead!
An endearing remark directed to siblings or one's own children; a child who is acting silly.
Example: Come over here you knucklehead(s)! I'm going to tickle you!