Thoughts black, hands apt, drugs fit, and time agreeing; Confederate season, else no creature seeing; Thou mixture rank, of midnight weeds collected, With Hecate’s ban thrice blasted, thrice infected, Thy natural magic and dire property On wholesome life usurp immediately.
There are no more uses of "usurp" in the play.
Show samples from other sources
Henry IV usurped the throne from Richard II while the latter was fighting in Ireland.
I believe there are more instances of the abridgement of the freedom of the people by gradual and silent encroachments of those in power than by violent and sudden usurpations.