Abbreviation for "also known as," useful when defining terms that are known under two or more names:

Shortwave radio, a/k/a World Band radio; or

Taiwan a/k/a Formosa.

Also pseudonyms vis-a-vis given names:

Victoria Beckham a/k/a Victoria Adams and Posh Spice.

A simplified use has more recently emerged: simply to type the letters. omitting the slashes (a/k/a "virgules") in between -- it is rare that anyone would confuse "aka" with a word called something like "akk-uh" and "aka" is easier to type:

David Johansen aka Buster Poindexter.

Reginald Dwight aka Elton John.

But both spellings are currently in use:

Do you have any biographical information about writer George Orwell, a/k/a (or aka) Eric Blair?

Although an abbreviation, note that no period is required.

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