Definition
An abetter is someone who aids, supports, or encourages another in some action or endeavor, often one that is wrong or illegal. They are like an accomplice who provides assistance or motivation to someone committing a crime or misdeed. The term is closely related to "abettor," and the two are often used interchangeably, though "abetter" may sometimes imply a more active role. Think of someone providing inside information for a heist or cheering on a bully. The abetter shares responsibility for the outcome. Unlike an innocent bystander, an abetter is complicit. They facilitate or promote the action in some way.