contractor
noun /kənˈtræktə(r)/,  /ˈkɒntræktə(r)/
  /ˈkɑːntræktər/
- a person or company that has a contract to do work or provide goods or services for another company
- a building/roofing/electrical contractor
 - a defence/security/military/civilian contractor
 - a private/an independent contractor
 - to employ an outside contractor
 
Extra Examplessee also subcontractor- We'll need to employ a building contractor to do the work.
 - a list of approved contractors
 
Oxford Collocations Dictionaryadjective- independent
 - private
 - external
 - …
 
- employ
 - hire
 - select
 - …
 
Word Originearly 16th cent.: from late Latin, from Latin contrahere ‘draw together’, from con- ‘together’ + trahere ‘draw’.