The word comes from the ancient Greek for “fixed impression.” Walter Lippmann (1889-1974), an American journalist, popularized the word, a printing-press term, as a metaphor for “a picture in our heads” that could be true or, more often, false. Examples of stereotypes include geisha, delivery boy, manicurist and Samurai (all used metaphorically).
REFERENCE: AAJA Handbook to Covering Asian America