De or het winstverwatering?

The correct Dutch article is:

de winstverwatering

Rule Words ending in -ing: almost always de. See the rule

How to use winstverwatering

the winstverwateringde winstverwatering
this winstverwateringdeze winstverwatering
that winstverwateringdie winstverwatering
our winstverwateringonze winstverwatering
your winstverwateringjouw winstverwatering
every winstverwateringelke winstverwatering
which winstverwatering?welke winstverwatering?
a big winstverwatering / the big winstverwateringeen grote winstverwatering, de grote winstverwatering