Someone who accedes to some act, now especially a crime; one who contributes as an assistant or instigator to the commission of an offense.
Accompanying as a subordinate; additional; accessory; especially, uniting in, or contributing to, a crime, but not as chief actor. See accessory.
A sidekick or subordinate, or the role of such a person.
The person playing second fiddle.
A fiddle part in harmony to the first fiddle.