How to capitalize (or not) an abbreviation, is there any rule?



Reading this article I was quite puzzled about the way the author capitalized or not the abbreviations.

When writing in full:

The Internet Corporation for Assigned Names and Number

All words are capitalized, but when abbreviating only the first letter is capitalized:

The Internet Corporation for Assigned Names and Number (Icann)

Following the article, there is an opposite situation:

generic top level domain.

Here, on the contrary the first letter is not capitalized while the rest are:

generic top level domain (gTLD).

Could you please explain if there are some rules on how to capitalize the abbreviations or it’s up to the author’s want?

Lucian Sava

Posted 2015-04-14T06:37:05.237

Reputation: 11 342

4ICANN themselves spell their abbreviated name in all caps, so I wonder why the beeb chose to spell it with only an initial capital — it looks strange to me. As for gTLD, this is a common style when you are dealing with a specific kind of something for which we have an established acronym (TLD). I realize this is not a full answer to your question, hence it's a comment. – oerkelens – 2015-04-14T07:32:10.617



This is, at least in part, a question of style. Or the style guides of, say, news organizations.

  • When you pronounce it as single letters, such as CNN (see en en) or BBC (bee bee see) it is usually written all caps.
  • When you pronounce it as one word some organizations write only capital letters, some spell it like a proper noun, first letter capitalized, rest lower case: CNN writes NATO, BBC writes Nato, as you say nato, not en ay tee oh.
  • There are lots of exceptions. SCSI is pronounced like a word, SKUZ-ee, but spelled upper case by the BBC, too.


Posted 2015-04-14T06:37:05.237

Reputation: 168

Your example that CNN writes NATO and BBC writes Nato is enough for me, so it's a matter of style. Thank you +1 – Lucian Sava – 2015-04-15T08:45:24.983


First point, these are acronyms not abbreviations. Here's an example of an acronym:

Federal Bureau of Investigation -> FBI

And here's an abbreviation:

Monsters Incorporated -> Monsters Inc.

The soft rule for acronyms is that every letter is upper-case and articles such as a/the/of/or are omitted. There are exceptions, the show Game of Thrones is abbreviated to GoT because GT is an acronym already associated with sports cars.

The Internet Corporation for Assigned Names and Number is probably referred to as Icann because the company want people to refer to it as "I can", rather than "The I.C.A.N.N." The unusual capitalization is to encourage people to see Icann as a pronounceable word.

What about gTLD? I think it's capitalized like this to underline the fact that this is a new type of TLD, not a new thing called a GTLD.


Posted 2015-04-14T06:37:05.237

Reputation: 4 357

Note that most people would simply call these abbreviations, which is fine. Some would call them acronyms, which sticklers would challenge. – Lucian Sava – 2015-04-14T10:43:00.737