The story
Etymology from Wiktionary, CC BY-SA 4.0.
Today it means: Any string of characters that has key (high) importance, such as a keyword or a keyphrase, but not necessarily a word in all senses of that term (as for example a phone number, an alphanumeric or numeric sequence, or string of symbols). Full definition →
Etymology from Wiktionary, CC BY-SA 4.0.