surface area
n. uncountable B2 Upper Intermediate
n. the total size of the outside layer of an object. You calculate it by adding up the areas of all the sides.
n. the total measure of the outer face or faces of a three-dimensional object. Used in geometry and physical sciences to determine rates of reaction or heat transfer.
Rough paper has more surface area than smooth paper.
The internal walls of the lungs have a massive surface area to allow for faster oxygen absorption.
In chemical engineering, increasing the surface area of a catalyst typically accelerates the reaction rate by providing more sites for molecular interaction to occur simultaneously.
Usage
Usually uncountable in general scientific contexts; may be countable when comparing the specific areas of multiple discrete objects.