To be accomplice to someone in an illegal act.(verb)
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Use "aid and abet" in a sentence
"I have told you all this to show you how we got so keen about soldiers, and why we sought to aid and abet the poor widow at the white cottage in her desolate and oppressedness."
"Just as the West offered Cold War–era support for Czechoslovakia’s Charter 77, right-side states can now aid and abet Belarus’s dissident group Charter 97."
"Sam, however, was willing to aid and abet me in strolling and lounging anywhere and at any hour, and lent a willing ear to my tales of what I saw, and had in his capacious wallet a pendent story or a spiritual precedent for anything that I could mention."