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Webster 1913 Edition
Thirlage
Thirl′age
,Noun.
 [Cf. 
Thrall
.] (Scots Law) 
The right which the owner of a mill possesses, by contract or law, to compel the tenants of a certain district, or of his sucken, to bring all their grain to his mill for grinding. 
Erskine.
 Webster 1828 Edition
Thirlage
THIRLAGE
,Noun.