After completing his service, he decided to pursue reenlistment for another term.

reenlistment 是由前缀 re-（表示“再次”）和 enlist（入伍、参军）组成的名词，enlist 本身由 en-（使进入）和 list（名单）构成。reenlistment 指“再次入伍”的行为或状态。