loftily

To a great height.

[…] trees, most of them bearing blossom or fruit, rose loftily into the air, and extended their broad leaves like parasols to the sun.

With affectation of grandness.

"I should never dream of calling a kid like you a woman," said Digory loftily.

"Can you play the violin?" asked Rosemary loftily, out of a chumbling refined mouth.