Greek numerical prefixes for groups

As well as supplying the prefixes in many English words for units of measurement and for geometrical figures, the Greek and Latin words for the numbers play a part - again often by supplying the prefix - in many other types of English word, in particular, in words for groups consisting of a certain number of objects or persons. (See Greek and Latin words for numbers, Prefixes in units of measurement, and Prefixes in words for geometrical figures.) For example, a group of six musicians is a sextet - sex is the Latin word for 'six'; a child who is one of four children born to the same mother at the same time is a quadruplet (often abbreviated to quad) - 'quadr-' comes from quattuor, the Latin word for 'four'; and a line of verse consisting of five metrical feet is a pentameter - pente is the Greek word for 'five'.

Here is a small selection of such words which make use of the Greek words for the numbers.:

• Rule by one, two, three, etc., individuals

Everyone knows the word monarchy, which means, literally, rule by a single individual: arche is the Greek for 'rule or sovereignty', and monos is the Greek word for 'alone or single'. Words for rule by a larger number of individuals are formed in the same way, using as prefixes the Greek words for the numbers. So rule by two individuals is a diarchy (or dyarchy), and rule by three, four, five, or six individuals is, respectively, a triarchy, tetrarchy, pentarchy, or hexarchy.

• Lines of verse

A line of verse with two metrical feet is a dimeter. A line of verse with three, four, five, or six metrical feet is, respectively, a trimeter, tetrameter, pentameter, or hexameter. The stem '-meter' comes from the Greek metron, which means 'measure'.

• Poems of two, three, etc., lines

A poem, or verse of a poem, composed of two lines is a distich. (A unit of two lines in a poem is also, and more commonly, referred to as a couplet.) Analogously, a poem, or verse, of three, four, five, or six lines is, respectively, a tristich, tetrastich, pentastich, or hexastich. The stem '-stich' comes from the Greek stichos, which means 'a row or file (e.g., of soldiers) or a line of verse'.

• Athletic contests

The pentathlon is an athletic contest in which the athletes must compete in five different events. But there is also a triathlon - a contest in which athletes must compete in three different events - and a heptathlon - a contest in which they must compete in seven different events. The stem '-athlon' comes from the Greek athlos, which means 'contest'.

For a small selection of similar words which make use of the Latin words for the Numbers see Latin numerical prefixes for groups.