大龄

older (than average in a group, at school, for marriage etc)

see 大夫[dai4 fu5]

big; large; great / older (than another person) / eldest (as in 大姐[da4 jie3]) / greatly; freely; fully / (dialect) father / (dialect) uncle (father's brother)

age / length of experience, membership etc

young people in their late 20s or older who are still unmarried