a.

1. 年长的，年纪较大的[（+to）]
   Bob is two years senior to me.

   鲍伯比我大两岁。

2. 地位较高的；年资较深的[（+to）]
   He is a senior member of the committee.

   他是委员会中的资深委员。

3. 【美】四年级生的；【英】高年级生的
4. 高级的；前辈的
   His father was a senior officer at the bank.

   他父亲是那家银行的高级职员。

5. （置姓名后表示年长者，常大写）老……，大……
   John Parker, Senior is the father of John Parker, Junior.

   老约翰·派克是小约翰·派克的父亲。

n.[C]

1. 较年长者
   Her boyfriend is her senior by six years.

   她的男朋友比她大六岁。

2. 前辈；上司；学长；资深人士
   He was my senior at Yale by two years.

   他是耶鲁大学比我高两级的学生。

3. 【美】（大学）四年级生；【英】（大学）高年级生
   The seniors defeated the juniors by 3-1.

   四年级学生以三比一战胜了三年级学生。

4. 【英】（大学）评议员

adj.

1. for or denoting older people.
   ▸Brit. for or denoting schoolchildren above a certain age, typically eleven.
   ▸US of the final year at a university or high school.
2. [postpos.] denoting the elder of two with the same name in a family.
3. high or higher in rank or status.

n.

1. a person who is a specified number of years older than someone else:
   she was two years his senior.
2. a student in one of the higher forms of a senior school.
3. (in sport) a competitor of above a certain age or of the highest status.
4. an elderly person, especially an old-age pensioner.