Definition of elongation in English:

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Pronunciation: /iːlɒŋˈɡeɪʃ(ə)n/


[mass noun]
1The action or process of lengthening something: the bird’s tails become forked through elongation of their outer feathers [count noun]: an elongation of the crater in the impact direction
More example sentences
  • Thus, the mechanical response in the adhesion geometry can be only partially estimated since adhesion induces strong elongations in the adhesive material.
  • To ensure that stressing was proceeding as expected, the testing agency measured the tendon elongations and compared them to the calculated elongations.
  • The lower maximum load used for calculation of graft elongations assured that values would be available for all specimens.
1.1An elongated part.
1.2The amount of extension of an object under stress, usually expressed as a percentage of the original length.
Example sentences
  • All structural metals have approximately the same ductility as measured by percentage elongation.
  • The relative amounts of elongation and spread cannot be calculated theoretically but they have been determined experimentally for mild steel.
  • Also ductility, as measured by percentage elongation, decreases.
2 Astronomy The angular separation of a planet from the sun or of a satellite from a planet, as seen by an observer: Mercury reaches greatest elongation on the 1st, when it will be 27 degrees west of the Sun
More example sentences
  • Furthermore, any resonance with the Earth is illusory in that Mercury is not well placed for observations except during its brief greatest elongations near its aphelion.
  • The planet reaches greatest eastern elongation, 23.5 degrees from the Sun, on the 3rd.
  • On the 9th the planet is at greatest elongation from the Sun and sets around two hours after the Sun.


Late Middle English: from late Latin elongatio(n-), from elongare 'place at a distance' (see elongate).

For editors and proofreaders

Line breaks: elong|ation

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