- A device for receiving or transmitting radio, television signals etc.
- of, or in, the air
- Automatic Frequency Control. (radio technics)
- Adult Foster Care
- American Football Conference
- Additional Finance Charges
- (Sometimes lower case) From Latin ante meridiem, meaning "before noon (12:00)".
- See also: A.M.
- Amplitude Modulation
- Contrasted with FM
- Assembly Member, a title similar to MP, placed after the name of a Member of the Welsh National Assembly.
- Artium Magister or Master of Arts
- lacking echos
- The basoonist settled into the chamber and prepared for another grueling recording session.
- The ratio of an object's longest dimension to its next-longest dimension.
- The ratio of width to height in a flat surface or 2-dimensional abstract construction, such as an image, character, or pixel. 4:3 (or 1.33:1) is the standard ratio for NTSC video. 1.85:1 and 2.35:1 are the most common aspect ratios for motion pictures.
- radio interference caused by pulses of electromagnetic radiation in the atmosphere as the result of lightning and other events (both natural and man-made)