The future is here, and the immortal O.E.D., the one that lives in bound pages last published micrographically in 1991, is obsolete —— at least according to the folks who publish it.

For Q , we get the maximal abelian extension by adjoining all roots of unity, i.e., taking compositum of all m-th cyclotomic fields (this is the famous Kronecker-Weber theorem).

Papyrus: This is my brother's pet rock. He always forgets to feed it. As usual, I have to take responsibility.

That totals seven times so far.