verb
(transitive) To enter (a name, etc.) in a register, roll or list
(transitive) To enlist (someone) or make (someone) a member of.
(intransitive or reflexive) To enlist oneself (in something) or become a member (of something).
(transitive, obsolete) To envelop; to enwrap.
(intransitive, zoology) To curl up into a ball.