This is also spelt 'Aneurin', the 'eu' sounding as 'ai' in most Indo-European languages. Traditionally it means blonde or golden haired. The origin is not 'Neirin'. That is the shortened version, the affectionate being simply 'Ni'.
-- Anonymous User 4/7/2005
Aneirin was a 7th century Welsh bard, serving the kings of the Old North (what is now modern lower Scotland). He wrote the epic Welsh poem 'Y Gododdin'.