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Webster 1913 Edition
Boation
Bo-a′tion
,Noun.
 [L. 
boatus
, fr. boare 
to roar.] A crying out; a roaring; a bellowing; reverberation. 
[Obs.] 
The guns were heard . . . about a hundred Italian miles, in long 
boations
. Derham.
Webster 1828 Edition
Boation
BOA'TION
,Noun.