-agh

From Old Irish -ach, from Proto-Celtic *-ākos, from Proto-Indo-European *-eh₂kos, *-eh₂ḱos, from a-stem suffix *-eh₂- + adjectival suffix *-kos, *-ḱos; compare Welsh -og. Doublet of -ag.

-agh

1. Forms nouns/adjectives from other nouns and adjectives with the sense of 'person or thing connected or involved with, belonging to, having'

   Nouns:

   • ‎Mannin (“Isle of Man”) + ‎-agh → ‎Manninagh (“Manxman/woman”)
   • ‎Sostyn (“England”) + ‎-agh → ‎Sostynagh (“Englishman/woman”)

   Adjectives:

   • ‎aash (“ease”) + ‎-agh → ‎aashagh (“easy”)
   • ‎firriney (“truth”) + ‎-agh → ‎firrinagh (“true”)

   Also:

   • Manninagh (“Manx”, adjective), Sostynagh (“English”, adjective)