mannered
Behaving in an unnatural, overly polite, or fake-sounding way.
Mannered describes someone whose behavior feels artificial or overly rehearsed, like they're performing politeness rather than genuinely expressing it. When someone is mannered, their gestures, speech, or social interactions seem stiff and calculated, as if they're following a script instead of acting naturally.
Imagine a student who always raises their hand with exaggerated slowness, speaks in an unnaturally formal voice, and bows slightly when greeting the teacher. While politeness is good, this mannered behavior feels like a performance. Similarly, an actor giving a mannered performance might deliver lines in a stilted, artificial way that reminds you they're acting instead of helping you forget and get lost in the story.
Having good manners and being mannered are different things. Good manners are natural and considerate. Mannered behavior feels forced, like someone trying too hard to seem sophisticated or proper. A person with genuine good manners makes others feel comfortable. A mannered person makes others notice how hard they're working to seem polite, which can create awkwardness.
Writers and artists use “mannered” as criticism. A mannered writing style is full of unnecessarily fancy words and complicated sentences that call attention to themselves. The goal of good writing, like good manners, is to communicate clearly and naturally, not to show off.