class act

plural class acts

1. An excellent performance.

   Tairawhiti Cultural Development Trust chairman Maui Tangohau said it was a class act by the national champions.

   2017 September 18, “Whangara Mai Tawhiti does it again”, in The Gisborne Herald, archived from the original on 03 Mar 2021

2. Someone or something whose performance is excellent.

   Rice is maturing at such a rate that he is now indispensable. Yes, these qualifiers may not be the most exacting examinations but he has also looked a class act at club level under manager David Moyes this season.

   2021 March 31, Phil McNulty, “England 2-1 Poland: What shape are Gareth Southgate's side in?”, in BBC Sport

3. sarcasticsometimesSomeone or something who is generally well-mannered, conscientious, etc.

   You can count on Sam to help out afterwards, he's a real class act.

   1 more example

   Oh yeah, they're a real class act; they left their garbage all over the grass.