Recursive acronym

A recursive acronym is an acronym (or occasionally, a backronym) which refers to itself in the expression for which it stands, similar to a recursive abbreviation. Though, because of their lack of a termination condition, perhaps a more accurate term would be circular acronym.

Computer-related examples

In computing, it soon became a hackish (and especially MIT) tradition to choose acronyms and abbreviations which referred humorously to themselves or to other abbreviations. Perhaps the earliest example in this context, from about 1977 or 1978, is TINT ("TINT Is Not TECO"), an editor for MagicSix. This inspired the two MIT Lisp Machine editors called EINE ("EINE Is Not Emacs") and ZWEI ("ZWEI Was EINE Initially"). (Note that in German "eine" means "one" (in the feminine form) and "zwei" means "two".)

More recent efforts include:

• Allegro — Allegro Low Level Game ROutines
• CAVE — Cave Automatic Virtual Environment
• Cygnus — Cygnus, Your GNU Support (though Cygnus says this is a backronym, while opponents maintain Cygnus, Your GNU Sucks)
• GEECS - GEECS for Electronics Engineering Computers and Science
• GiFT — GiFT: Internet File Transfer, unofficially: "GiFT Isn't FastTrack"
• GiNaC — GiNaC is Not a CAS
• GNE — GNE is Not an Encyclopedia!
• GNU — GNU is Not Unix!
• KIEL — Kiel Integrated Environment for Layout
• LAME — LAME Ain't an MP3 Encoder
• LIAR, a Scheme compiler — LIAR Imitates Apply Recursively
• LINE - LINE is Not an Emulator, a utility to run Linux programs on Windows
• MICO — MICO Is COrba
• MINC — MINC Is Not C
• MINCE — MINCE is Not Complete Emacs
• MiNT — MiNT is Not TOS (later changed to "MiNT is Now TOS")
• mung — Mung Until No Good (backronym, based on an earlier backronym "Mash Until No Good")
• NiL — NiL Isn't Liero
• PHP — PHP: Hypertext Preprocessor (another backronym - originated as "Personal Home Page" tools)
• PINE — Pine Is Not Elm (according to Pine's author, this is a backronym)
• PLD — PLD Linux Distribution (originally "Polish(ed) Linux Distribution")
• PNG — PNG is Not GIF (another backronym - originated as "Portable Network Graphic")
• RESPECT - Respect, Equality, Socialism, Peace, Environmentalism, Community, and Trade unionism.
• RPM — RPM Package Manager (originally "Red Hat Package Manager")
• Scaled — Scaled Composites: Advanced Link to Efficient Development
• SPARQL — SPARQL Protocol And RDF Query Language
• TINA — Tina Is No Acronym, or This Is No Acronym
• TINN — Tinn Is Not Notepad
• TRM — TRM Recognizes Music
• TTP — The TTP Project (from Dilbert)
• Wine — Wine Is Not an Emulator (backronym, originally Windows Emulator)
• YAML — YAML Ain't Markup Language (initially "Yet Another Markup Language")
• Zinf — Zinf Is Not FreeA*p!

The GNU Hurd project is named with a mutually recursive acronym: "GNU" stands for "GNU is Not Unix", "Hurd" stands for "Hird of Unix-Replacing Daemons," and "Hird" stands for "Hurd of Interfaces Representing Depth."

Recursive acronyms appeared in a Dilbert comic strip, in which Dilbert states that the TTP project refers to The TTP Project (this is also a triply-redundant case of RAS syndrome).

A number of recursive acronyms are backronyms, which used to expand to a different string but whose expansion changed once the acronym was well-known, for one reason or another, to one which included the acronym itself. This includes at least PHP and RPM.

Other variations on this theme can be found in the following phrases from the electronics industry...

• LCD Display - Liquid Crystal Display Display
• IDC Connector - Insulation Displacement Connector Connector

Non-technical examples

Recursive acronyms are not limited to computing terminology. For example, some corporations have been (re)named in this way:

• TAP Airlines — TAP Air Portugal (in Portuguese, TAP is acronym to Transportes Aéreos de Portugal and is not recursive)
• BWIA — BWIA West Indian Airways (formerly British West Indian Airways)
• VISA — Visa International Service Association
• OIL -Oil India Limited

There are also some organizations that employ recursive acronyms:

• MOMS Club — MOMS Offering Moms Support

Finally, it should be noted that TIARA Is A Recursive Acronym.

Recursive Powers of LISP

Recursive acronyms have been known to be used as examples to demonstrate the recursive powers of LISP. For example, Douglas Hofstadter uses tato in several of his articles from his Metamagical Themas.

By substituting the phrase 'tato (and tato only)' for every occurrence of tato, you end up with:

n=0: tato
n=1: tato (and tato only)
n=2: tato (and tato only) (and tato (and tato only) only)
n=3: tato (and tato only) (and tato (and tato only) only) (and tato (and tato only) (and tato (and tato only) only) only)

etc.

See also

RAS syndrome (Redundant Acronym Syndrome syndrome)