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Glite Dictionary
📏 Half main axis 📏 Half longest diameter
semimajor

semimajor

8.1
Relating to half of the longest line across an ellipse
  • adjective
  • /ˌsɛmiˈmeɪdʒər/
  • Specialized
translation icon : semimayor
  • In an ellipse, the semimajor axis is crucial for determining its overall size.

Examples

  • The distance from the center of an ellipse to its edge along the semimajor axis is called the focal radius.

  • The periods of the planetary orbits increase as the 3/2 power of their semimajor axes.

    Academic text (2003)

  • Astronomers use the length of the semimajor axis to calculate the orbits of celestial bodies.

Compounds

semimajor axis
  • Specialized
8.0

The distance from the center of an ellipse or oval to its farthest edge, equal to half the longest diameter

Surface Forms

semimajor positive

Morphology

semimajor = major (transparent) = semi + major

The meaning follows the standard prefix semi- plus major, referring to half of the major axis.

Etymology

Semimajor comes from the parts semi- 'half' and major 'large', so as an adjective it describes the 'half' of the larger part of an ellipse. That's why a semimajor axis means the half of the ellipse's longest diameter.