How can I call "trivial" quadrics, like empty set, single point, straight line, plane, two lines, two planes...?

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My temptation is to call it degenerate quadrics. But, in Wikipedia, the list of degenerate quadrics also includes cylinders and conic quadrics. On the other hand, in these notes, the author uses the term degenerate as I would use: only for quadrics that are finite unions of "euclidean primitive objects" (points, straight lines and planes). Is this terminology acceptable?