Ordovician

劍橋詞典

from or referring to the period of time between about 485 and 445 million years ago, in which there were many different types of animals in the sea , including vertebrates (= animals with back bones ), but no life on land
奧陶紀(jì)的（距今約4億8千5百萬年至4億4千5百萬年前間，此時(shí)水中已有許多動(dòng)物包括脊椎動(dòng)物，但是陸地上還沒有動(dòng)物）
the Ordovician period 奧陶紀(jì)
Ordovician fish 奧陶紀(jì)的魚類

the Ordovician

noun [ 單數(shù)名詞 ]

the Ordovician period
奧陶紀(jì) 返回 Ordovician