The abutment is the part of a structure that holds or supports the weight of other parts that are putting horizontal or vertical pressure on the structure itself.
A vertical abutment is most easily observed in the structure of a bridge.
For houses, an example of abutment is where the verge or upper edge of a pitched roof meets a balustrade.
On a smaller scale it can also be found on various types of furniture that will hold a lot of weight.
They are critical in the building of homes and structures as failing to realize the need for them can result in catastrophic failure of the construction.