Show to be out of place (10)
I believe the answer is:
Here is my best explanation:
'show' is the definition.
'out of place' is the subsidiary indication.
'out of' becomes 'ex'.
'place' becomes 'position' (positioning is a kind of placing**).
'to be' is the link.
(Other definitions for exposition that I've seen before include "large show", "Account", "fair", "Commentary", "Show", "Display", "commentary" and "Public display".)