I'm about to stay in the same place (6)
I believe the answer is:
ibidem
'in the same place' is the definition.
('ibidem' can be a synonym of 'in the same place')
'i'm about to stay' is the wordplay.
'about' means one lot of letters goes inside another.
'to stay' becomes 'bide' (biding is a kind of staying).
'im' enclosing 'bide' is 'IBIDEM'.
(Other definitions for ibidem that I've seen before include "In the same place as previous reference" , "Previously cited (in this book)" , "In the same book or passage, often abbreviated" , "In the same place (in references)" , "In the same source (Lat.)" .)