'contractor-built' originates from the combination of 'contractor' and 'built', where 'contractor' refers to a person or company that undertakes a contract to provide materials or labor to perform a service or do a job, and 'built' is the past participle of 'build', meaning to construct.

'contractor' comes from the Latin word 'contractus', meaning 'drawn together', and 'built' is derived from the Old English 'byldan', meaning 'to construct'.

Initially, 'contractor-built' simply referred to any structure built by a contractor, but over time it has come to imply a certain level of professionalism and quality in construction.