Synonyms for affectation

These nouns refer to personal behavior assumed for effect. An affectation is artificial behavior, often adopted in imitation of someone, that is perceived as being unnatural: “His [Arthur Rubinstein's] playing stripped away . . . the affectations and exaggerations that characterized Chopin interpretation before his arrival” (Michael Kimmelman).
Pose denotes an attitude adopted to call favorable attention to oneself: His humility is only a pose.
Air, meaning a distinctive but intangible quality, does not always imply sham: The director had an air of authority.
In the plural, however, it suggests affectation and self-importance: The movie star was putting on airs.
Mannerism denotes an idiosyncratic trait or quirk, often one that others find obtrusive and distracting: His mannerism of closing his eyes as he talked made it seem as if he were deep in thought.