An archaic or rare form meaning a confederate, ally, or one who confederates with others.
From Latin con- (together) + foederatus (allied, from foedus meaning covenant or treaty). This abbreviated form is largely obsolete in modern English.
This rare form shows how Latin-derived words often had multiple English variants before standardization—'confeder,' 'confederate,' and even 'confederator' all competed to describe the same concept.
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