senior² n 1 be two/five/ten etc years sb's senior to be two, five, ten etc years older than someone 比某人大两岁/五岁/十岁等 2 [C] AmE a student in the last year of HIGH SCHOOL or college 【美】 〔高中或大学里〕毕业班的学生 → compare 比较 JUNIOR² 3 [C] AmE a senior citizen 【美】 老年人