Quorum is the Latin word for “of whom.” It has the double-meaning of “a select group” and “the number (such as a majority) of officers or members of a body that when duly assembled is legally competent to transact business.”
In biology, the term “quorum sensing” refers to the mechanism by which bacteria communicate and regulate their behavior. They send and receive chemical signals from other bacteria, and once their population reaches a certain number, they are able to do things as a group that would be impossible for a single bacterium. As such, it is the process by which the many seek one another out in order to act as one.
What's a quorum, anyways?
As a choir, we seek one another out in much the same way. Individual voices can not perform harmony alone, but assembled together as a quorum of voices, we are able to sing a full spectrum of choral works.