Does "nullity" have a potentially conflicting or confusing usage? In Linear Algebra and Its Applications, David Lay writes, "the dimension of the null space is sometimes called the nullity of A, though we will not use the term." He then goes on to specify "The Rank Theorem" as "rank A + dim Nul A = n" instead of calling it the the rank-nullity theorem and just writing "rank A + nullity A = n".
Naturally, I wonder why he goes out of his way to avoid using the term "nullity." Maybe someone here can shed light....

Maybe he just doesn't like the idea of using jargon for the dimension of a specific subspace? It's not a particularly useful piece of jargon.
