'ANSI' originates from English, specifically the initialism of 'American National Standards Institute'.

'ANSI' formed as an initialism for the organization's full name. The organization traces back to earlier bodies such as the American Engineering Standards Committee (AESC) and the American Standards Association (ASA) and adopted the name 'American National Standards Institute' in its modern form.

Initially it referred specifically to the organization's formal name; over time it has also come to label standards, encodings, and attributes associated with that organization (e.g., 'ANSI standard', 'ANSI encoding').