[5] In the grand Irish epic of the Tain Bo Cuailnge, Neman confounds armies, so that friendly bands fall in mutual slaughter.
When the forces of Queen Medb arrive at Magh-Tregham, in the present county of Longford, on the way to Cuailnge, Nemain appears amongst them: “Then the Neman attacked them, and that was not the most comfortable night with them, from the uproar of the giant Dubtach through his sleep.
And in another passage, in the episode called "Breslech Maighe Muirthemhne,” where a terrible description is given of Cuchullain's fury at seeing the hostile armies of the south and west encamped within the borders of Ulaid, we are told (Book of Leinster, fol.54, a2, and b1): Nemain is an Irish goddess who is very powerful.
"He saw from him the ardent sparkling of the bright golden weapons over the heads of the four great provinces of Eriu, before the fall of the cloud of evening.
And the Neman confused the army; and the four provinces of Eriu dashed themselves against the points of their own spears and weapons, so that one hundred warriors died of fear and trembling in the middle of the fort and encampment that night."
Squire (2000:45) glossed the name as 'venomous' presumably relating it to the Proto-Celtic *nemi- 'dose of poison' 'something which is dealt out' from the Proto-Indo-European root *nem- 'deal out' (Old Irish nem, pl.