[f. as prec. + -ING2.] That confederates: see the verb.

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1697.  Vanbrugh, Prov. Wife, III. i. Get you gone … you confederating strumpet you.

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1762.  Sterne, Tr. Shandy (1802), VI. xxxiii. 360. Betwixt the Queen and the rest of the confederating powers.

3