ellipsoidilla
ellipsoidilla is a term that can refer to a few different concepts, primarily within the fields of mathematics and geometry. Most commonly, it is the instrumental case of the word "ellipsoid." An ellipsoid is a quadric surface that is the three-dimensional generalization of an ellipse. It is a surface defined by the equation (x^2/a^2) + (y^2/b^2) + (z^2/c^2) = 1, where a, b, and c are the lengths of the semi-axes. In this context, "ellipsoidilla" would describe something being done *with* or *by means of* an ellipsoid.
For example, one might encounter the phrase "calculating the volume ellipsoidilla," meaning the volume is calculated