” I think a character actor is one who traditionally plays non-leading man/lady roles, such as the sidekick, the leading man’s best friend, the comic foil, the butler, etc.”
Gotcha. I suppose one should categorize actors.
Leading man/woman
Comic actors(including those who do drama and comedy with equal ease)
Character actors/sidekicks
One of my favorite character actors is one of Preston Sturges’s favorite “mugs,” Bill Demarest.