One of the pictures on a strip of photographic film, or one of the single pictures that together form a television or cinema film. Cambridge Dictionary
Stop-motion is an animation technique in which objects (2D or 3D) are physically manipulated. The object (or parts of the object) are moved in small increments between individually photographed frames. When the series frames are played as a fast sequence they create the illusion of movement.
A peg bar is a piece of plastic, wood or metal that holds your cels and backgrounds in place when you draw and shoot your animation. Chew, Johnny. “What is A peg bar?” ThoughtCo, Lifelong Learning. 26 July 2016.
A combination of a cel, or cels, and background. A set-up may also include additional elements from a scene, such as overlays or special effects. S/R Laboratories Animation Art Conservation Center. Nomeclature
Animation artwork is a term used to describe any of the many forms of artwork that are involved in the making of an animated film Finch, C., & Rosenkrantz L. (1998) Sotheby’s Guide to Animation Art. New York: Henry Holt.