something used to improve the appearance of something
veneer - cover
The word ‘veneer’ in a literal sense refers to a thin layer of decorative wood or plastic that covers the surface of something to make it look better. However, the term is more commonly used in a figurative sense to express a superficial act, appearance, or effect used deceptively to conceal something unpleasant or unwanted.
The salesperson was a crook, but with his smart suit and clean-cut appearance, he managed to hide who he really was under a veneer of respectability.
The panels of the car were of inferior quality, but they were given an oak veneer which made them look quite elegant.
Times of crisis and hardship can often reveal what our society is really like under the thin veneer of civilization.