Ham Radio Slang, Abbreviations and On-Air Jargon

Amateur radio has accumulated a rich vocabulary over more than a century of operation. Some terms come from the telegraph era, some from military radio, some from the early days of broadcasting, and some are purely home-grown ham culture. This reference covers the slang, abbreviations and jargon every ham should know — from the meaning of 73 to what an Elmer is.

The number 73 is one of the most recognised expressions in amateur radio and it predates radio itself. It originated as a telegraph brevity code in 1857 — part of a system of numerical codes published by the Western Union Telegraph Company where each number stood for a common phrase. Code 73 meant “best regards.” Telegraph operators adopted it enthusiastically and it carried directly into wireless telegraphy and then amateur radio, where it has been in continuous use for over 165 years.

You will hear 73 used at the end of virtually every contact: “73 de W1AW” or simply “seventy-three” on phone. Saying “seventy-threes” with an S is technically incorrect since 73 is already a complete phrase, but it is so commonly heard that pointing it out is considered pedantic.

The term Elmer for a ham radio mentor first appeared in print in a 1971 QST article by Rod Newkirk W9BRD, who used the name to describe a helpful older ham who guided newcomers into the hobby. The name stuck and is now universal in amateur radio culture worldwide. Having an Elmer is considered one of the best ways to learn the hobby, and being an Elmer — mentoring a new operator — is one of the most valued contributions a experienced ham can make to the community.

When a ham radio operator dies, they are said to have become a Silent Key — their key (Morse code key) is forever silent. The term appears in club newsletters, QRZ memorial pages, and obituaries throughout the amateur radio world. It is a respectful and deeply felt expression of loss in the community. The CW prosign SK (end of contact) shares the same letters but is a different usage; in the context of a deceased operator, SK is always written out as “Silent Key.”