It is a T shaped structure with spindle fibers attached to it. The spindle fibers reach out to grab chromosomes during the cell cycle.
The Centroid definition is a much clearer one. The object’s Centroid is the physical center. In engineering, we use centroid when you need to locate the core of an entity. If it has one symmetry point, the controls in that dimension will be in. If it has two axes of symmetry then the centroid is the point of intersection of the two axes. We have formulas to find the same, for irregular shapes.