Conspiratrix

“That most impious conspiratrix, the countess of Buchan [Isabella MacDuff] being likewise apprehended, the king commanded that, since she had not used the sword, her life should be spared; but, in regard of her illegal conspiracy, she should be confined in a building constructed of stone and iron,[…]”

Source: wiktionary

The soldier of fortune, with whom Queen Christina, when they were both in exile, conspired to overturn the comparatively quiet and decorous rule of [Baldomero] Espartero’s Regency, has since that undergone vicissitudes that illustrate the condition of his country: his arbitrary insolence made his presence intolerable; he was overreached by the superior finesse of the intrigante, and driven from the kingdom; he has returned to be spectator of a grand intrigue, which triumphed, but now serves him as a pretext for crying down his fellow-conspiratrix; and it is his turn to try the trick of banishing an inconvenient accomplice.

Source: wiktionary

“I should have murdered him, or he would have murdered me, by this time! It is impossible to say how I hate the villain!” returned Lady Mulgrave, with an energy that bore testimony to the sincerity of her expression. / “Well, I know of a capital revenge we could take on him,” said the conspiratrix.

Source: wiktionary

“We will not summon her,” interposed the Prior of St. John at Dalkeith: “we all hold her to be unworthy of credence—a false speaker—an unmaidenly person—a convicted conspiratrix⸺”

Source: wiktionary