To set up; found. See Synonyms at found1. To bring about; generate: establish goodwill in the neighborhood. To place or settle in a secure position or condition; install: They established me in my own business. To make firm or secure. To cause to be recognized and accepted: a discovery that established his reputation. To introduce and put (a law, for example) into force. To prove the validity or truth of: The defense attorneys established the innocence of the accused. To make a state institution of (a church).