Tlachtga
Version 1
Kilbride MS 3, Advocates' Library, Edinburgh

Tlachtgha whence named? Moghruith [the wizard's] d. Tlachtgha, whom (when with her father she went to study magic in the eastern world) Simon Magus's sons all three had to wife, even she it was that for Trén constructed the roth rámhach, the flagstone that is Forchartha, and the cauldron in Cnámchoill. Then she, bringing with her these two last, returned out ff the E. and reached [the present] tulach Tlachtgha; here she lay in and three sons were born : Dorib, a quo mágh nDoirbi; Cuma, a quo mágh gCuma; Muach, a quo mágh Muaich; so long as which names subsist in the men of Erin's memory, vengeance of outside strangers shall not attain Ireland. She died in childbed and over her the dún was erected, hense Tlachtgha.

SOURCE:
Silva Gadelica. trans. and ed. by Standish O'Grady. p 511, III. p48.