Canonical (adjective)

1. Following or in agreement with accepted, traditional standards.
2. Officially recognized or sanctioned by the Church.

Origin:

Early 15c., from latin canonicus "pertaining to a rule or standard", from canon "rule, standard" (see canon (n.)). originally in reference to the texts of scripture recognized as genuine and authoritative by the church, and later extended to other fields.

Examples:

1. The novel is considered a canonical text in literature.
2. The work is considered canonical for understanding the artist's work.
3. The Canonical Gospels are considered authentic by the Christian Church.
4. The Canonical hours are the divisions of the day in monastic life of the western church.
5. The Canonical form is the standard form of a mathematical expression.