[1] : The Collaborative International Dictionary of English v.0.48

trona \tro"na\, n. of egyptian or north african origin. chem.
    min.
   a native double salt, consisting of a combination of neutral
   and acid sodium carbonate, na2co3.2hnaco3.2h2o, occurring
   as a white crystalline fibrous deposit from certain soda
   brine springs and lakes; -- called also urao, and by the
   ancients nitrum.
   1913 webster
see also:
na2co3.2hnaco3.2h2o urao nitrum 

[2] : The Collaborative International Dictionary of English v.0.48

urao \ura"o\, n. sp. min.
   see trona.
   1913 webster urare
see also:
trona 

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