Everybody initially occupying a Clackmannanshire town (5)
I believe the answer is:
alloa
'clackmannanshire town' is the definition.
(I've seen this before)
'everybody initially occupying a' is the wordplay.
'everybody' becomes 'all' (all people).
'initially' indicates taking the first letters.
The initial letter of 'occupying' is 'o'.
'all'+'o'+'a'='ALLOA'
(Other definitions for alloa that I've seen before include "possible cup opponent" , "A few thousand Scots" , "Central Scottish town" , "Town on Firth of Forth" , "Athletic club" .)