If you happen to be at the nexus of something, this noun means that you are right in the middle.
A nexus is a noun that stands for something at the center or that which others are gathered around. The word entered English during the seventeenth century from the Latin word nectere and means "to bind, tie." In the field of cell biology, a nexus refers to "a specialized area of the cell membrane involved in intercellular communication and adhesion," and implies that the nexus of a cell facilitates communication among the various parts and allows it to work properly.