Stereotype

DEF: A set, preconceived idea about people or things.

EX: 1. He doesn’t conform to the usual stereotype of the businessman with a dark suit and briefcase. 2. You may have big surprises if you stereotype all Hollywood actors as tall, handsome men.

Merriam-Webster Online Dictionary
stereotype (verb)
transitive verb
1.
to make a stereotype from
2.
a) to repeat without variation make hackneyed
b) to develop a mental stereotype about
stereotype (noun)
1.
a plate cast from a printing surface
2.
something conforming to a fixed or general pattern , especially a standardized mental picture that is held in common by members of a group and that represents an oversimplified opinion, prejudiced attitude, or uncritical judgment