Quote:

depending in whether you've accepted the prevalent meaning shift Ohhh, no no no--don't tell me that! IS NGO an acronym, or ISN'T it? I want to know; no gray area allowed.

Initialisms--thanks, zmjezhd.



this graying of meaning is a work in process; e.g., MW-CD has initialism as an also meaning for acronym, while AHD4 still distinguishes between the two, although you have to look up both words to get the distinction. OED2 contrasts the two, but only if you look up initialism -- this is from the 1989 ed., they won't get to the As (or Is) in their updates for some time.

then there's Wiki:
"Initialism" originally referred to abbreviations formed from initials, without reference to pronunciation, but during the middle portion of the twentieth century, when acronyms and initialisms saw more use than ever before, the word "acronym" was coined for abbreviations which are pronounced as a word, like "NATO" or "AIDS". The term "initialism" is now typically taken to refer to abbreviations which are pronounced by sounding out the name of each constituent letter (e.g., HTML). However, in general usage, "acronym" is used by some speakers and writers to cover both forms, while others prefer to observe a difference. In addition, to many users, "initialisms" are also simply known as "abbreviations".

There is no agreement as to what to call abbreviations that contain single letters, but can otherwise be pronounced as a word, such as JPEG (jay-peg) or MS-DOS (em-ess-doss). These abbreviations are sometimes referred to as acronym-initialism hybrids, although they are grouped by most under the broad meaning of "acronym".