Sense of position, say (5)
I believe the answer is:
sight
'sense' is the definition.
(sighting is a kind of sensing)
'position say' is the wordplay.
'position' becomes 'site' (site is a kind of position).
'say' indicates a 'sounds like' (homophone) clue.
'site' is a homophone of 'SIGHT'.
'of' acts as a link.
(Other definitions for sight that I've seen before include "Range of vision" , "View" , "The ability to see - spectacle" , "monstrosity" , "Vista" .)