A cartoon character starting with A is Apu.
Underdog?
Alice from Alice in wonderland
abner Alley Oop
a cartoon character starting with the letter M could be mickey mouse , minnie mouse
Prime meridian.
Kenny from South Park
itchy from "itchy and skratchy"
elmer fudd
Bugs Bunny
Rajah the tiger from Aladdin.
Kim Possible Krazy Kat
Charlie Brown (Peanuts)