This is either a pun or a misreading of the name. According to the Four Masters, Art O'Melaghlin, lord of Westmeath, was killed by Dermot mac Toirdhealbhach O'Brien that year.
| From Annales Dominicani de Roscoman (Author: [unknown]), ms page 45v (Year .DAR1184.2) | Corpus of Electronic Texts Edition Close footnote |