A Mechanic

1. (now chiefly historical) A manual worker; a labourer or artisan. [from 16th c.]
2. Someone who builds or repairs machinery, a technician; now specifically, someone who works with and repairs the mechanical parts of a motor vehicle, aircraft or similar. [from 17th c.]
3. A device, command, or feature which allows someone to achieve a specific task. [from 20th c.]
4. A hit man. [from 20th c.]
5. (gambling) A cheat who manipulates the cards or dice