enlist

enlist
en‧list /ɪnˈlɪst/ verb
1. [transitive] to persuade someone to help you to do something
    enlist sb’s help/services etc
    He has enlisted the help of a sports psychologist for the team.
    The public are being enlisted to help.
2. [intransitive, transitive usually passive] to join the army, navy etc
    enlist as
    He enlisted as a private.
    enlist in
    At the outbreak of war, he was enlisted in the army.
—enlistment noun [uncountable and countable]