noun🔗Share光年 A unit of length (abbreviation ly; equal to just under 10 trillion kilometres (1016 metres)) equal to the distance light travels in one Julian year; used to measure extremely large distances."Astronomers estimate that the galaxy is about 100,000 ly across. "天文学家估计这个星系的直径大约是十万光年。astronomyphysicsspaceunitsciencemathChat with AIVocabulary GamePractice Reading
noun🔗Share远路，长途。 (only in plural) A very long way."The marathon runner in the lead is light years ahead of the one at the back."领先的马拉松选手把最后面的选手远远甩在了后头，他们之间差着十万八千里。wayspaceplaceChat with AIVocabulary GamePractice Reading
noun🔗Share久远， 很久。 (only in plural) A very long time."Some of Leonardo da Vinci’s inventions were light years ahead of their time."莱昂纳多·达·芬奇的一些发明在很久很久以前就远超他的时代。timepastChat with AIVocabulary GamePractice Reading
