Usually an English-style initial name formed from letter initials rather than a traditional single-name etymology.
Aj is the phonetically respelled form of AJ, itself most commonly a set of initials used as a given name — a distinctly American naming tradition that gained momentum through the 20th century as parents sought names that were informal, punchy, and resistant to the formality of full given names. The initials could stand for any number of name combinations: Andrew James, Anthony John, Alexandra Jane — the possibilities are as open as the name itself, which is part of its appeal. By writing it as Aj rather than the initialisms AJ, parents signal that this is a proper name in its own right, not an abbreviation.
In Hindi and Sanskrit traditions, Aj (अज) means "unborn" or "without birth" — an epithet applied to Brahma and Vishnu denoting their eternal, self-existent nature. This gives the name, when used in South Asian contexts, a profound theological weight that its casual Western usage rarely acknowledges. The name Ajay, widely used across India, derives from the same root combined with *jaya* ("victory"), meaning "invincible" — and Aj often functions as its natural diminutive.
As a standalone Western given name, Aj occupies a relaxed, confident space. It is the kind of name that introduces itself easily, sounds comfortable in every social register, and carries no particular historical burden. In an age when parents are gravitating toward short, phonetic names that work across cultures, Aj has a certain stripped-down logic — a name that simply sounds like itself, and means whatever the person inside it makes of it.