Discrimination against people of height. A set of attitudes and behaviors that act out or seek to reinforce that discrimination. The different treatment of people on the grounds of their physical stature. The belief that people of different physical statures are fundamentally different.
A set of pseudoscientific theories that seek to give validity and credibility to that discrimination.
Heightism: A belief that height is a potential measure of human traits, capabilities, or intellect and that height differences produce an inherent superiority of taller individuals.
"Does that 5'3" fool really think he can whoop that 6'4" 280lb man?"
The deceptive act of making Tom Cruise appear taller and making actors appear shorter to play elves, dwarfs, or other short characters instead of casting someone who's of shorter stature and would more accurately portray the part.