Noun

(en noun)

An elongated depression between hills or mountains, often with a river flowing through it.

* {{quote-magazine, date=2013-08-16, author= John Vidal

, volume=189, issue=10, page=8, magazine=(The Guardian Weekly) , title= Dams endanger ecology of Himalayas , passage=Most of the Himalayan rivers have been relatively untouched by dams near their sources. Now the two great Asian powers, India and China, are rushing to harness them as they cut through some of the world's deepest valleys .}}

The area which drains into a river.

Any structure resembling one, e.g., the meeting point of two pitched roofs.

The internal angle formed by the intersection of two sloping roof planes.

Noun

(en noun)

A generally accepted principle; a rule.

The trial must proceed according to the canons of law.

* Shakespeare

Or that the Everlasting had not fixed His canon 'gainst self-slaughter.

(literary) A group of literary works that are generally accepted as representing a field.

(turn into real quote) "the durable canon of American short fiction" — William Styron

The works of a writer that have been accepted as authentic.

the entire Shakespeare canon

A eucharistic prayer, particularly the Roman Canon.

A religious law or body of law decreed by the church.

We must proceed according to canon law.

A catalogue of saints acknowledged and canonized in the Roman Catholic Church.

In monasteries, a book containing the rules of a religious order.

A member of a cathedral chapter; one who possesses a prebend in a cathedral or collegiate church.

A piece of music in which the same melody is played by different voices, but beginning at different times; a round.

Pachelbel’s ''Canon'' has become very popular.

(fandom) Those sources, especially including literary works, which are generally considered authoritative regarding a given fictional universe.

A spin-off book series revealed the aliens to be originally from Earth, but it's not canon .

(cookery) A rolled and filleted loin of meat.

a canon of beef or lamb

(printing) The largest size of type with a specific name, formerly used for printing the canons of the church.

(senseid)The part of a bell by which it is suspended; the ear or shank of a bell.

(Knight)

(billiards) A carom.