depot vs machine room

depot

noun
  • A storage facility, in particular, a warehouse. 

  • A bus station or railway station. 

  • A place where recruits are assembled before being sent to active units. 

  • A storage space for public transport and other vehicles where they can be maintained and from which they are dispatched for service 

  • A place for the storage, servicing or upgrade of military hardware. 

  • The portion of a regiment that remains at home when the rest go on foreign service. 

  • The tableau; the area where cards can be arranged in solitaire or patience games. 

machine room

noun
  • A limited-access room in a larger building dedicated to HVAC equipment and other machinery. 

  • A dedicated room for computers and related data processing equipment, often having a raised floor, abundant and dedicated air conditioning, and specialized power supply and fire suppression systems. 

How often have the words depot and machine room occurred in a corpus of books? (source: Google Ngram Viewer )