age out
v. phr.β Β«Amy Weldon is whatβs called a rook-out, a first-year rookie whoβs aging out of the corps. She says her firstβand last yearβhas offered her memories that will last a lifetime.Β» ββDrum Corps Groups March Out of Madison After Championships” by Dana Brueck WMTV-TV (Madison, Wisconsin) Aug. 12, 2006. (source: Double-Tongued Dictionary)