軌き道どう離り心しん率りつ

noun

orbital eccentricity

Technical term in astronomy describing how much an orbit deviates from a perfect circle.

• この惑わく星せいの軌き道どう離り心しん率りつは非ひ常じょうに小ちいさいため、ほぼ円えん軌き道どうを描えがいている。

  Because this planet's orbital eccentricity is very small, it follows a nearly circular orbit.

• 軌き道どう離り心しん率りつが大おおきいほど、楕だ円えん軌き道どうは細ほそ長ながくなる。

  The larger the orbital eccentricity, the more elongated the elliptical orbit becomes.