theatrical
Overly dramatic, like acting in a play on stage.
Theatrical means overly dramatic or exaggerated, like a performance on stage. When someone makes a theatrical gesture, they might throw their arms wide and gasp loudly instead of just saying “oh no” quietly. A theatrical sigh involves slumping your whole body and making sure everyone notices your disappointment.
The word comes from theater, where actors project their voices and make big movements so audiences can see and hear them clearly from far away. But when someone acts theatrical in everyday life, they're treating a normal moment like it belongs on stage. If your friend discovers they forgot their lunch and drops to their knees wailing “I'm doomed!”, that's theatrical behavior.
Theatrical can also simply mean related to theater and drama. A theatrical production is a play or performance. Theatrical makeup is the special cosmetics actors use on stage. Someone with a theatrical career works in theater as an actor, director, or designer.
The difference matters: calling a performance theatrical is neutral or positive (it's supposed to be dramatic), but calling someone's everyday behavior theatrical suggests they're being unnecessarily dramatic. When your sister practices her theatrical speech for the school play, that's appropriate. When she delivers the same dramatic performance because she has to set the table for dinner, that's theatrical in a different way.