Order
- Legal and military meanings
- Scientific meanings
- Order (biology)
- In computing, canonical order
- In information processing, order is a measure of the number of objects or sub-systems in a system as seen by an observer.
- Mathematical meanings
- Order (mathematical) of an ordered set; see also total order and total preorder
- Order (mathematical) of a group or its elements. See order (group theory).
- Order (mathematical) of an element in some modulus, see multiplicative order
- Order of a differential equation
- Big O notation (mathematical), aka the order of an algorithm
- Miscellaneous meanings
- Order (philosophy)
- Order (business)
- Order (religious)
- Holy Orders
- Order (military)
- Architectonic orders: see classical orders
- Ordered sets of pitches or pitch classes such as a tone row, see the mathematical meaning above.