Change round to sounding pompous (7)

I believe the answer is:

orotund

I'm a little stuck... Click here to teach me more about this clue!

'pompous' is the definition.
(I've seen this before)

'change round to sounding' is the wordplay.
'round to' anagrams to 'OROTUND'.
Though, I am unsure how the anagram is indicated.

Can you help me to learn more?

(Other definitions for orotund that I've seen before include "Sonorous; pompous" , "Full in sound" , "Full, clear and musical" , "Pompous (in style)" , "Resonant" .)

I've seen this clue in The Globe and Mail.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.