Below is a list of plain English guides and glossaries for Legal Terms:
National Adult Literacy Agency provides this Guide (Downloadable PDF at the link)
The Plain English Campaign has a similar A-Z Guide
Courts Service, Law Society and Lawyer.ie all provide glossaries of legal terms.
http://ulsites.ul.ie/law/law-resources-international-students This page is provided by the University of Limerick for international students studying law.
Online legal dictionaries can be helpful for understanding different legal terms.
However when citing exercise caution and consult the National College of Irelands Referencing Guide for more information.