A number of six-footers in occupation (7)
I believe the answer is:
tenants
'a number of six-footers in occupation' is the definition.
I can't judge whether this definition defines the answer.
'a number of six-footers in' is the wordplay.
'a' becomes 'an'.
'number of six footers' becomes 'tents' (I can't explain this - if you can you should give a lot more credence to this answer).
'in' is an insertion indicator.
'an' going into 'tents' is 'TENANTS'.
Can you help me to learn more?
(Other definitions for tenants that I've seen before include "They pay rent" , "Lodgers" , "Occupiers" , "residents" .)