The most common and most likely answer to this crossword clue is the 9 letter word AMPLITUDE
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More clues leading to the result AMPLITUDE
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The cryptic/wordplay part
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What does AMPLITUDE mean?
AMPLITUDE noun- The measure of something's size, especially in terms of width or breadth; largeness, magnitude.
- The maximum absolute value of the vertical component of a curve or function, especially one that is periodic.
- The maximum absolute value of some quantity that varies.
- The arc of the horizon between the true east or west point and the center of the sun, or a star, at its rising or setting. At the rising, the amplitude is eastern or ortive: at the setting, it is western, occiduous, or occasive. It is also northern or southern, when north or south of the equator.
- The arc of the horizon between the true east or west point and the foot of the vertical circle passing through any star or object.
- The horizontal line which measures the distance to which a projectile is thrown; the range.