grúg, grúig
Definitions (by source)
grúig [14], grúg, wrinkle, frown, anger 17 32; WW, DiD, AOD xxii 10, S xxvii 15.
Aithdioghluim Dána: A Miscellany of Irish Bardic Poetry, Historical and Religious, including the Historical Poems of the Duanaire in the Yellow Book of Lecan. Vol II, Translations, Notes, Vocabulary. Editor: Lambert McKenna S.J.
m., anger, hatred, 2300, 6646
Trí Bior-Ghaoithe an Bháis: The Three Shafts of Death. Editor: Osborn Bergin.