Intact, entire (8)
I believe the answer is:
integral
I believe this is a double definition.
'intact' is the first definition.
(I know that intact can be written as integral)
'entire' is the second definition.
(I know that entire can be written as integral)
(Other definitions for integral that I've seen before include "Formed of constituent parts" , "Triangle (anag)" , "Large tin (anag.)" , "Built-in -- 1 across (anag)" , "Triangle being essential" .)