Initial word
An initial word is an abbreviation consisting of the initial letters of several words. Examples: o.a., s.o.z., please, btw.
Abbreviating words has primarily a practical use. Familiar abbreviations are easier to read than the full word, and an abbreviation also takes up less space. With abbreviated company names and brand names, it is often hardly known what the letters stand for. Examples: KPN, ABN AMRO, ING, KLM.
If the letters of the abbreviation when pronounced form a new word, we call it an acronym or acronym. Examples: HAVO, pin, pc ("peesee").
An abbreviation consisting of several letters of one word is an abbreviation.