Etymologically
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phase

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Pronunciation

  • IPA: /feɪz/[1]

Etymology

It is a back-formation, as a singular, from New Latin phasēs, the plural of phasis,[2][3][4] perhaps in part from French phase,[3][5][6] from Ancient Greek φάσις (phásis, “appearance of a star, phase of the moon”),[2][3] from the stem of φαίνειν (phaínein, “to show, make appear”),[2][3][4] from Proto-Indo-European *bha- (“to shine”).[2][4] The Latin singular phasis was used in English from 1660.[2] It is related to phantom, fantasy and phenomenon.[3][7]

Earliest recorded meaning

A phase of the moon, the appearance the moon or a planet presents at a given time: 1705 in Etymonline,[2] 1812 in the OED and Barnhart,[8][3] and 1647 in Merriam-Webster.[9]

Semantic evolution

The modern sense, a distinct period, had developed by 1701 according to Word Origins;[10] Etymonline, Barnhart and the OED date the general sense “aspect, stage of development” to 1841.[2][3][8] In physics, a stage in a recurring sequence of movements, it is from 1861,[2][8] and a distinct homogeneous form of matter from 1875.[8] A temporary difficult period, especially of adolescents, is from 1913.[2][8] The verb, “to adjust the phase of, synchronize”, is from 1895 in Etymonline,[2] 1938 in the OED and Barnhart,[8][3] and “to carry out gradually, in stages” is from 1949,[2][3][8] giving phase in and phase out in 1954.[2] Phase was also an erroneous spelling of faze from 1889.[8]

Timeline

  • 1705 – a phase of the moon.[2]
  • 1841 – a stage of development.[2][8]
  • 1861 – in physics.[2][8]
  • 1913 – a difficult period.[2][8]
  • 1949 – verb, to carry out in stages.[2][3]
  • 1954 – phase out.[2]

Modern meaning

Noun

  1. A distinct stage of development.
  2. A temporary manner, attitude or pattern of behaviour: just a phase.
  3. An aspect or part.
  4. One of the recurring apparent forms of the moon or a planet.
  5. In physics, a particular stage in a periodic process, as of a wave.
  6. In chemistry, a distinct and homogeneous form of matter in a system.

Verb

  1. To plan or carry out in stages: phased in over two years.
  2. To synchronize.

Word family

  • phasic
  • phaseless
  • single-phase
  • three-phase
  • phase-in
  • quarter-phase
  • two-phase
  • diphase
  • phantom
  • fantasy
  • phenomenon
  • emphasis
  • faze

Usage notes

The American Heritage distinguishes phase, which may denote a change in the thing itself, from aspect, facet, angle and side, ways of viewing it.[11]

References

  1. ^ Jones, Daniel (2011), Cambridge English Pronouncing Dictionary, 18th ed., ed. Peter Roach, Jane Setter and John Esling, Cambridge: Cambridge University Press
  2. ^ a b c d e f g h i j k l m n o p q r Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  3. ^ a b c d e f g h i j Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
  4. ^ a b c The American Heritage Dictionary of the English Language (2000), 4th ed., Boston: Houghton Mifflin
  5. ^ Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
  6. ^ Soanes, Catherine; Stevenson, Angus, eds. (2004), Concise Oxford English Dictionary, 11th ed., Oxford: Oxford University Press
  7. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
  8. ^ a b c d e f g h i j k Simpson, J. A.; Weiner, E. S. C., eds. (1989), The Oxford English Dictionary, 2nd ed., Oxford: Clarendon Press
  9. ^ Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
  10. ^ Cresswell, Julia (2021), Oxford Dictionary of Word Origins, 3rd ed., Oxford: Oxford University Press
  11. ^ The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin