Glut, surplus (13)
I believe the answer is:
overabundance
I believe this is a double definition.
'glut' is the first definition.
(I've seen this before)
'surplus' is the second definition.
(I've seen this before)
(Other definitions for overabundance that I've seen before include "Excess quantity" , "Surplus, excess" , "Excessive quantity" , "Glut" .)