This is the 6185th most frequent Chinese word.
年滿
"年滿" means "to reach a specified age."
In this sentence, '年满' is used to indicate the specific age at which someone becomes eligible for an activity (turning 18 and voting).
他年满十八岁，就可以投票了。
He will be eligible to vote when he turns 18.
Here, '年满' specifies an age requirement set for eligibility to enter a location or partake an activity.
会员需年满二十一岁才能进入该场馆。
Members must be at least 21 years old to enter this facility.
In this context, '年满' denotes reaching the threshold age to access special benefits or services designed for seniors.