Also, mathematics' naming conventions are quite strict. The nabla symbol is almost-exclusively used for vector-calculus operations. The letters t, s, u, v are

Also, mathematics' naming conventions are quite strict. The nabla symbol is almost-exclusively used for vector-calculus operations. The letters t, s, u, v are almost-always used for parametrizations. The letters i, j, k, n, m are usually used as indices of summations. We can go on.