A classical order is one of the ancient styles of classical architecture

Classical antiquity

Classical antiquity is a broad term for a long period of cultural history centered on the Mediterranean Sea, comprising the interlocking civilizations of ancient Greece and ancient Rome, collectively known as the Greco-Roman world...

, each distinguished by its proportions and characteristic profiles and details, and most readily recognizable by the type of column

Column

A column or pillar in architecture and structural engineering is a vertical structural element that transmits, through compression, the weight of the structure above to other structural elements below. For the purpose of wind or earthquake engineering, columns may be designed to resist lateral forces...

 employed. Three ancient orders of architecture—the Doric

Doric order

The Doric order was one of the three orders or organizational systems of ancient Greek or classical architecture; the other two canonical orders were the Ionic and the Corinthian.-History:...

, Ionic

Ionic order

The Ionic order forms one of the three orders or organizational systems of classical architecture, the other two canonic orders being the Doric and the Corinthian...

, and Corinthian

Corinthian order

The Corinthian order is one of the three principal classical orders of ancient Greek and Roman architecture. The other two are the Doric and Ionic. When classical architecture was revived during the Renaissance, two more orders were added to the canon, the Tuscan order and the Composite order...

—originated in Greece. To these the Romans added the Tuscan

Tuscan order

Among canon of classical orders of classical architecture, the Tuscan order's place is due to the influence of the Italian Sebastiano Serlio, who meticulously described the five orders including a "Tuscan order", "the solidest and least ornate", in his fourth book of Regole generalii di...

, which they made simpler than Doric, and the Composite

Composite order

The composite order is a mixed order, combining the volutes of the Ionic order capital with the acanthus leaves of the Corinthian order. The composite order volutes are larger, however, and the composite order also has echinus molding with egg-and-dart ornamentation between the volutes...

, which was more ornamental than the Corinthian. The order of a classical building is akin to the mode

Musical mode

In the theory of Western music since the ninth century, mode generally refers to a type of scale. This usage, still the most common in recent years, reflects a tradition dating to the middle ages, itself inspired by the theory of ancient Greek music.The word encompasses several additional...

 or key

Key (music)

In music theory, the term key is used in many different and sometimes contradictory ways. A common use is to speak of music as being "in" a specific key, such as in the key of C major or in the key of F-sharp. Sometimes the terms "major" or "minor" are appended, as in the key of A minor or in the...

 of classical music

Classical music

Classical music is the art music produced in, or rooted in, the traditions of Western liturgical and secular music, encompassing a broad period from roughly the 11th century to present times...

, the grammar

Grammar

In linguistics, grammar is the set of structural rules that govern the composition of clauses, phrases, and words in any given natural language. The term refers also to the study of such rules, and this field includes morphology, syntax, and phonology, often complemented by phonetics, semantics,...

 or rhetoric

Rhetoric

Rhetoric is the art of discourse, an art that aims to improve the facility of speakers or writers who attempt to inform, persuade, or motivate particular audiences in specific situations. As a subject of formal study and a productive civic practice, rhetoric has played a central role in the Western...

 of a written composition.