A decorative moulding used between a wall and ceiling line.
Crackle finish
Special finishing paint formulated to shrink and form cracks in the dry film exposing the underneath colour.
Usually applied to furniture to leaving a distressed finish.
Results similar appearance to mud cracking.
Cratering
Caused by rain falling onto a semi dry paint film or aeration of a paint coating during application. 
The formation of ridges and hollows in a paint or varnish coating.Cross Hatch Adhesion Testing
Cross Hatch Adhesion Testing
A cross hatch adhesion test is used to check the adhesion of a coating over the applied substrate. 
This is by drawing over the surface the cutting blades and then firmly applying clear adhesive tape applied over the hatch markings
and on removal the adhesion result is based on the amount of paint product is removed .
For further information see: https://www.elcometer.com/en/coatings-inspection/all-coatings-inspection.html
Cross Lining
Hanging lining paper horizontally to cover surface imperfections before hanging standard wallpaper in a vertical direction.
Wrinkling of the paint film which forms a pattern similar to a crow's foot.
Cup Gun
A conventional air assisted spray gun with the paint supplied from a reservoir fitted either on top or underneath the gun.
Curing
The time mixed materials such as concrete and two pack paints i.e. epoxy and polyurethane coatings take to dry by chemical action.