Monarch to have something going on tomorrow (5)

I believe the answer is:

crown

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

'something going on tomorrow' is the definition.
I can't tell whether this defines the answer.

'monarch to have' is the wordplay.
'monarch' becomes 'cr' (short for Carolus Rex, King Charles in Latin).
'to have' becomes 'own' (to have something is to own it).
'cr'+'own'='CROWN'

Can you help me to learn more?

(Other definitions for crown that I've seen before include "repair for damaged tooth" , "piece of tooth" , "Old coin; top of tree" , "Summit" , "Headdress, coin" .)

I've seen this clue in The Times.

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.