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Webster 1913 Edition
Unprotestantize
Un-prot′es-tant-ize
,Verb.
T.
[1st pref.
un-
+ protestantize
.] To render other than Protestant; to cause to change from Protestantism to some other form of religion; to deprive of some Protestant feature or characteristic.
The attempt to
unprotestantize
the Church of England. Froude.