1 a wonderful and surprising person or thing:
the marvels of nature / technology
2 (marvels) [pl.] wonderful results or things that have been achieved:
The doctors have done marvels for her.
verb (-ll-, AmE -l-) ~ (at sth) to be very surprised or impressed by sth: [V] Everyone marvelled at his courage. [also Vthat, Vspeech]
