[1] : Easton's 1897 Bible Dictionary

ulai
   the eulaus of the greeks; a river of susiana. it was probably
   the eastern branch of the choasper kerkhan, which divided into
   two branches some 20 miles above the city of susa. hence daniel
   8:2,16 speaks of standing "between the banks of ulai", i.e.,
   between the two streams of the divided river.
   

[2] : Hitchcock's Bible Names Dictionary (late 1800's)

ulai, strength; fool; senseless

Ulai >> U Words
Ulai, definition of term: Ulai
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