en·list 
(ĕn-lĭst)
(ĕn-lĭst)v. en·list·ed, en·list·ing, en·lists
v.tr.
1. To engage (persons or a person) for service in the armed forces.
2. To engage the support or cooperation of.
v.intr.
1. To enter the armed forces.
2. To participate actively in a cause or enterprise.
en·listment n.