Definitions

from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun The 21st letter of the Greek alphabet.

from The Century Dictionary.

  • noun The Greek letter φ, corresponding to the English ph .
  • noun The Greek letter φ, corresponding to the English ph .

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun The twenty-first letter of the Classical and Modern Greek, the twenty-second letter of Old and Ancient.
  • noun A visual illusion caused by lights turning on and off in a sequential pattern that implies motion.
  • noun mathematics The symbol for the golden ratio.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun the 21st letter of the Greek alphabet

Etymologies

from The American Heritage® Dictionary of the English Language, 4th Edition

[Late Greek phī, from Greek phei.]

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Examples

  • The number is termed phi, and like its brother pi, the order of its digits is mysteriously unending and seemingly nonrepeating.

    The G.O.D. Experiments Gary E. Schwartz 2006

  • Yeah, I’m thinking an LPhi-phi is more my speed JWiaDH.

    THE ‘OH FACE’ GUY GETS WORK. SORT OF. 2008

  • One of the most remarkable metapatterns that replicate throughout nature and the universe is defined by the numerical ratio termed phi.

    The G.O.D. Experiments Gary E. Schwartz 2006

  • One of the most ubiquitous metapatterns in nature—a pattern that follows the “Golden Ratio” called phi—is the universal spiral shape that appears in the trails made by subatomic particles, in the double-helix molecule DNA, in seashells, in the movement pattern of the heart, in tornadoes, in galaxies.

    The G.O.D. Experiments Gary E. Schwartz 2006

  • One night, a little after twelve o'clock, as he was on the point of going to bed like any plain citizen of regular habits, his Majesty fell to thinking how most accurately to render into English the troublesome Siamese word phi, which admits of a variety of interpretations.

    The English Governess at the Siamese Court Leonowens, Anna H 1870

  • The book is a fascinating story of the history and present understanding of the golden ratio, i.e. the number "phi", or 1.6180339887......

    The Golden Ratio and design Erik Stolterman 2005

  • In art it is possible to find "phi" in so many instances, and of course in architecture.

    The Golden Ratio and design Erik Stolterman 2005

  • In art it is possible to find "phi" in so many instances, and of course in architecture.

    Archive 2005-11-01 Erik Stolterman 2005

  • The book is a fascinating story of the history and present understanding of the golden ratio, i.e. the number "phi", or 1.6180339887......

    Archive 2005-11-01 Erik Stolterman 2005

  • If the point of the tongue be placed between the teeth, and air from the mouth be forced between them, the Th sibilant is produced, as in thigh, and should have a proper character, as [TN: Looks like the Greek 'phi'].

    The Temple of Nature; or, the Origin of Society A Poem, with Philosophical Notes Erasmus Darwin 1766

Comments

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  • Greek letter symbol for the irrational number known also as the "golden ratio": 1.618033989...

    It is derived by calculating:(sqrt 5) plus-or-minus 1, all divided by 2.

    The golden ratio can be characterized as, a:b::b:(a+b), or, using actual figures:

    .618... :1 :: 1 : 1.618...

    December 5, 2006

  • The actual "Golden Ratio" is (1+sqrt(5)) / 2, which is 1.618...

    December 6, 2006

  • Also an acronym for Protected Health Information, mandated by HIPAA legislation.

    October 29, 2007

  • The remains of King Philippe III, beheaded in 1629.

    October 20, 2008