The feminine affix ūṅ comes in denoting a Name after a prātipadika (Nominal Stem) ending with the word bāhu,
Thus भद्रबाहूः 'Bhadrabahu'; जालबाहूः &c. Why do we say in \expressing a Name\? Observe वृत्तबाहूः 'a woman having rounded hand' which is an attributive word. In other words, when the compound is a name, बाहु takes long ऊ in the feminine.,