Definitions

1. noun

A base or foundation, especially one that is below or beneath something else.

“The subbase of the road was made of compacted gravel.”

2. noun

In mathematics, especially algebra and geometry, the subbase of a topological space is a subset of its base that generates the topology.

“The subbase of the topological space was used to derive a new theorem.”

3. noun

In chemistry, a subbase is a compound that can accept a proton, acting as a base in a chemical reaction.

“The subbase of the acid-base reaction played a crucial role in determining the pH level.”