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Webster 1913 Edition
Mastress
Mas′tress
,Noun.
 Mistress. 
[Obs.] 
Chaucer.
 Webster 1828 Edition
Mastress
MASTRESS
, for mistress, is not used.Definition 2025
mastress
mastress
English
Noun
mastress (plural mastresses)
-  Obsolete form of mistress.
- (Can we find and add a quotation of Chaucer to this entry?)