Perhaps one Munich let out (9)
I believe the answer is:
lunchtime
'perhaps one' is the definition.
Although both the answer and definition are singular nouns, I don't understand how one could define the other.
'munich let out' is the wordplay.
'out' is an anagram indicator (out can mean wrong or inaccurate).
'munich'+'let'='munichlet'
'munichlet' anagrammed gives 'LUNCHTIME'.
Can you help me to learn more?
(Other definitions for lunchtime that I've seen before include "When to take a short break" , "Maybe one" , "When midday meal is eaten" , "Midday break" , "free period?" .)