扁へん平ぺい率りつへんぺいりつMeanings1nounoblateness; flatteningTechnical term in geometry and astronomy for the degree to which a spheroid is flattened at the poles.地ち球きゅうの扁へん平ぺい率りつは約やく二に百ひゃく九きゅう十じゅう八はち分ぶんの一いちです