Casters out to obtain one to play a part (7)

I believe the answer is:

actress

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

'obtain one to play a part' is the definition.
I can't judge whether this definition defines the answer.

'casters out' is the wordplay.
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'casters' anagrammed gives 'ACTRESS'.

'to' acts as a link.

Can you help me to learn more?

(Other definitions for actress that I've seen before include "dame on stage?" , "Recasts (anag) - performer" , "Terry, say" , "Female player" , "eg Emma Thompson" .)

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.