Definition of underact in English:
Act a part in a play or film in an overly restrained or unemotional way.
- I think this movie may mark the only time in recorded history when he managed to underact in a part.
- It's a caper film, with all the obligatory touchstones of the genre and everyone underacts to great effect.
- DeNiro underacts brilliantly, creating a character whose obsessive concern for control and order is both his means to the top and his undoing.
Definition of underact in:
- US English dictionary