Categories: Lists of three-character combinations Intermediate distribution frame (IDF): In a central office or customer premises, a frame that (a) cross-connects the user cable media to individual user line circuits and (b) may serve as a distribution point for multipair cables from the main distribution frame (MDF) or combined distribution frame (CDF) to individual... In telecommunication, Telephony encompasses the general use of equipment to provide voice communication over distances. ... An American HH-60 Pavehawk working with the Icelandic Coast Guard. ... The Irish Defence Forces are the army, navy and air force of the Republic of Ireland. ... The Israel Defense Forces are part of the Israeli Security Forces. ... The AIDC F-CK Indigenous Defence Fighter (also known as Ching-kuo 經國, after late ROC President Chiang Ching-kuo), is a military aircraft produced by the Aerospace Industrial Development Corporation based in Taichung for the Republic of China Air Force in 1994 along the same general lines as the F... It has been suggested that Apocopation be merged into this article or section. ... Acronyms and initialisms are abbreviations, such as NATO, laser, and LED, written as the initial letter or letters of words, and pronounced on the basis of this abbreviated written form. ... Acronyms and initialisms are abbreviations, such as NATO, laser, and LED, written as the initial letter or letters of words, and pronounced on the basis of this abbreviated written form. ... Most three-letter English words are only one syllable long; however, there are certain exceptions such as emu and era. ...