Mahaabaahu महाबाहु Mahaabaaho महाबाहो BG 10:1

A Sanskrit dictionary defines Mahaabaahu as long-armed, powerful. 

Shri Krishn was addressing Arjun as Mahaabaaho. It was a qualitative reference to the powerful personality of Arjun who had long arms that were the characteristics of an excellent archer who needed long arms to stretch the bow to the maximum.

In Mahaabaaho, single-A should be pronounced as U in But, whereas double-A should be pronounced as A in Bata.