Terce and sext for example, or a longer stretch of the day (6,5)
I believe the answer is:
office hours
'a longer stretch of the day' is the definition.
I can't tell whether this definition defines the answer.
'terce and sext for example' is the wordplay.
I cannot really see how this works, but
'sext for example' could be 'hour' (sext is a kind of hour) and 'hour' is present in the answer.
The remaining letters 'offices' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'or' is the link.
Can you help me to learn more?
(Other definitions for office hours that I've seen before include "Time spent working" , "Say, nine to five" .)