Enrolment
Part of speech: noun
Definition: The act of enrolling or the state of being enrolled The people enrolled, considered as a group The number of people enrolled The record of such enrolling; registration
Registration
Part of speech: noun
Definition: the act of signing up or registering for somethingthat which registers or makes something official, e.g. the form or paper that registersalignment, e.g. of colors or other elements in a printing processthe location where guests register, especially with a hotel.
Example sentence: After almost half a billion dollars spent on the computer registration system for Obamacare, the website coughed, sputtered, and appeared to descend into an immediate coma as millions tried to log on. One reason is that the Obama administration never fully tested it.