Translation according to P. W. Joyce:
Lis, Liss (Irish Lios), an ancient fort. See vol. i.p. 271. In the majority of cases the second part of a ik's - name is personal, viz. the name of the person who owned the lis when it got the name. The interpretation of many such names is obvious at a glance : no one could mistake the meaning of such names as Lismacrory, Lisdonnell, Lisgorman, and hundreds like them. The most usual gen. of lios is leasa, but sometimes we find gen. lis or less, which when occurring in names is pronounced Ui>\ as in Letter-tinlish and Tullylish.