cardinal
noun [ C ] uk/ˈkɑː.dɪ.nəl/ us/ˈkɑːr.dɪ.nəl/
(PRIEST)
（罗马天主教会的）红衣主教，枢机主教
a priest of very high rank in the Roman Catholic Church
Cardinals elect and advise the Pope. 红衣主教们推选教皇并担当教皇的顾问。
(NUMBER)
(also cardinal number)基数
a number that represents amount, such as 1, 2, 3, rather than order, such as 1st, 2nd, 3rd
Compare: ordinal
(BIRD)
红衣凤头鸟（见于北美，雄鸟有鲜红色的羽毛）
a North American bird, the male of which has bright red feathers
cardinal
adjective [ before noun ] uk/ˈkɑː.dɪ.nəl/ us/ˈkɑːr.dɪ.nəl/
极重要的；基本的；主要的
of great importance
a cardinal rule/error/sin 基本规则／根本错误／严重错误
Synonym: key