Keyword (linguistics), word which occurs in a text more often than we would expect to occur by chance alone
Keyword (computer programming), word or identifier that has a particular meaning to the programming language
Keyword (cryptography), word used as the key to determine the letter matchings of the cipher alphabet to the plain alphabet
Index term, a term used as a keyword to retrieve documents in an information system such as a catalog or a search engine
Keyword (rhetoric), a word that academics use to reveal the internal structure of an author's reasoning
Keywords: A Vocabulary of Culture and Society, 1973 non-fiction book by Raymond Williams