D.n. = Doctor (in academical degrees, as a Latin word following, and as English preceding, other initials), as D.D. (Divinitatis Doctor), Doctor of Divinity, LL.D. (Legum Doctor), Doctor of Laws, M.D. Doctor of Medicine, Ph.D., Doctor of Philosophy, D.C.L., Doctor of Civil Law, D.Lit., Lit.D., Doctor of Literature, D.Phil., Doctor of Philosophy, D.Sc., Doctor of Science.