Many of these abbreviations come from CW (see below!) operating, especially in the early days of amateur radio. Just as in the early days of texting on a mobile phone without word completion, shorthand was used.
|Letters used by an operator when calling and looking for a contact with another radio amateur.
|Continuous Wave - more familiarly known as Morse. It's not really continuous wave, since you have to break it up into the dahs and dits to communicate information.
|Distance communication. This can mean around the World, across the Atlantic, or just across the Irish Sea, depending on the frequency band and so on being used.
|Frequency modulation. Popular in handheld radios, but greedy on the batteries, since when transmitting a full power signal is transmitted all the time.
|Old man. Any (male) radio amateur.
|The person operating the amateur radio station.
|Single sideband. Popular for voice DX communication, since it's economical with the power; if there's no sound, there's no signal!
|"Ex-Young Lady"! Normally used to mean the (male) operator's wife. Don't often hear of an XYM ... but then there are not as many YL operators as there should be.