B1
to treat an illness or injury by cutting someone's body and removing or repairing part of it
Dictionary examples:
The vet operated on my cat. Now it barks! (0.0)
They operated on my brain, but found nothing inside! (0.0)
The doctor operated on my singing voice. Now I sound like a frog! (0.0)
Did they have to operate on him? (20.6)