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Webster 1913 Edition
Countergage
Coun′ter-gageˊ
(-gājˊ)
, Noun.
 (Carp.) 
An adjustable gage, with double points for transferring measurements from one timber to another, as the breadth of a mortise to the place where the tenon is to be made. 
Knight.
 Webster 1828 Edition
Countergage
COUNTERGAGE
,Noun.