# elongation

/ˌiɫɔŋˈɡeɪʃən/ (US) · /ɪləŋɡˈeɪʃən/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/elongation
Updated: 2026-10-16

## Definition

a stretch that makes something longer, or the process of becoming longer. You use it when something grows or pulls longer in one direction.

For teachers: a lengthening or stretching of something in one direction, or the resulting increased length. In astronomy, refers to the angular separation between the Sun and another body as viewed from Earth.

## Examples

- Heat causes the elongation of the metal rod.
- The physical therapist measures the elongation of the muscle as the patient stretches his leg.
- Astronomers waited for the planet's greatest eastern elongation, when Mercury would appear farthest from the Sun's glare and briefly visible after sunset.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.