Crossword Genius

Former nun is retiring, becoming pensioner? (7)

Ross

I believe the answer is:

oldster

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

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

'former nun is retiring' is the wordplay.
'former' becomes 'old' (both can mean previous).
'nun' becomes 'rets' (I can't explain this - if you can you should believe this answer much more).
'is retiring' says the letters should be written in reverse.
'rets' back-to-front is 'ster'.
'old'+'ster'='OLDSTER'

'becoming' acts as a link.

Can you help me to learn more?

(Other definitions for oldster that I've seen before include "Senior citizen (mainly US)" , "One aged" , "Experienced person" , "one getting on" , "One no longer inexperienced" .)

I've seen this clue in The Telegraph.
Want a hint initially instead of a full solution? Install my app