- Order (biology)
- Order (business)
- Order (government)
- Order (military)
- Order (polynomial)
- Order (religious)
- Order (mathematical) of an ordered set; see also total order and total preorder
- Order (mathematical) of a group or its elements. See Glossary of group theory
- Order (mathematical) of an element in some modulus, see Multiplicative order
- architectonic orders - see Classical orders
- Court order
- Big O notation (mathematical) - also known as the order of an algorithm
- In computing, canonical order
- Executive order
- General order
- Standing order