Translation according to P. W. Joyce:
Cahernahoon in Galway ; Cathair-na-huamhan, of the cave. For such caves, see Caherhenryhoe. See Úamha, uamhain, vol. i. p. 438 [reproduced below].
There is yet another word for a cave in very general use, which I find spelled in good authorities in three different ways, uagh, uaimh, and uath [ooa]; for all these are very probably nothing more than modifications of the same original. There is a class of romantic tales in Irish "respecting various occurrences in caves: sometimes the taking of a cave, when the place has been used as a place of refuge or habitation; sometimes the narrative of some adventure in a cave; sometimes of a plunder of a cave; and so on" (O'Curry, Lect., p. 283). A tale of this kind was called uath, i.e. cave. The second form uaimh is the one in most general use, and its genitive is either uamha or uamhain [ooa, ooan], both of which we find in the annals. Cloyne in Cork, has retained only part of its ancient name, Cluain-uamha, as it is written in the Book of Leinster and many other authorities, i.e. the meadow of the cave; this was the old pagan name, which St. Colman MacLenin adopted when he founded his monastery there in the beginning of the seventh century; and the cave from which the place was named so many hundred years ago, is still to be seen there. At A. M. 1350, the Four Masters record the erection by Emhear, of Rath uamhain, i.e. the fort of the cave (O'Donovan's Four Masters I., 27), which exhibits the second form of the genitive. Both of these genitives are represented in our present names. The first very often forms the termination oe or oo, or with the article, nahoe; as Drumnahoe in Antrim and Tyrone, and Drumahoe in Derry, i.e. Druim-na-huamha, the ridge of the cave; Farnahoe near Inishannon in Cork (Farran, land); Glennoo near Clogher in Tyrone and Glennahoo in Kerry, the glen of the cave. And occassionally the v sound of the aspirated m comes clearly out, as in Cornahoova in Meath, and Cornahove in Armagh, the round-hill of the cave; the same as Cornahoe in Monaghan and Longford. The other genitive, uamhain [ooan], is also very often used, and generally appears in the end of names in the form of one or oon, or with the article, nahone or nahoon; in this manner we have Mullennahone in Kilkenny and Mullinahone in Tipperary, Muilenn-na-huamhain, the mill of the cave, the latter so called from a cave near the village through which the little river runs: Knockeenahone in Kerry (little hill); and Lisnahoon in Roscommon, so called, no doubt from the artificial cave in the lis or fort. Both forms are represented in Gortnahoo in Tipperary, and Gornahoon in Galway, the field of the cave; and in Knocknahoe in Kerry and Sligo, and Knocknahooan in Clare, cave hill.