Noun

(en noun)

The name of the sixteenth letter of the Classical and Modern Greek alphabets and the seventeenth in Old Greek.

(mathematics) An irrational and transcendental constant representing the ratio of the circumference of a Euclidean circle to its diameter; approximately 3.1415926535897932384626433832795; usually written .

(metal typesetting) Metal type that has been spilled, mixed together, or disordered. Also called pie.

Noun

(label) Endlessness, unlimitedness, absence of end or limit.

A number that has an infinite numerical value that cannot be counted.

* {{quote-magazine, date=2012-01

, author=Michael Riordan , title=Tackling Infinity , volume=100, issue=1, page=86 , magazine= citation , passage=Some of the most beautiful and thus appealing physical theories, including quantum electrodynamics and quantum gravity, have been dogged for decades by infinities' that erupt when theorists try to prod their calculations into new domains. Getting rid of these nagging ' infinities has probably occupied far more effort than was spent in originating the theories.}}

An idealised point which is said to be approached by sequences of values whose magnitudes increase without bound.

(label) A number which is very large compared to some characteristic number. For example, in optics, an object which is much further away than the focal length of a lens is said to be "at infinity", as the distance of the image from the lens varies very little as the distance increases further.

(label) The symbol .