Sheer, the Parisian church tower (7)
I believe the answer is:
steeple
'church tower' is the definition.
(I've seen this before)
'sheer the parisian' is the wordplay.
'sheer' becomes 'steep' ('steep' can be similar in meaning to 'sheer').
'the parisian' becomes 'le' (definite article in French).
'steep'+'le'='STEEPLE'
(Other definitions for steeple that I've seen before include "Tall building" , "Pointed structure" , "Pet eels (anag)" , "point" , "Jack up this?" .)