1. 直升机
A chopper is a helicopter.

1. a grounder that bounces high in the air

Synonym: chop

2. a butcher's knife having a large square blade

Synonym: cleavermeat cleaver

3. an aircraft without wings that obtains its lift from the rotation of overhead blades

Synonym: helicopterwhirlybirdeggbeater

4. informal terms for a human `tooth'

Synonym: pearly