Definition of roof jack in English:

roof jack

noun

North American
  • 1A platform or other support erected on a roof to facilitate repair, painting, etc.

  • 2A smoke vent of a chimney; (also) an airtight fitting attached to the roof and joining the internal and external sections of a vent pipe.

  • 3A pole supporting the roof of a tent. rare.

Origin

Late 19th century; earliest use found in The San Francisco Chronicle. From roof + Jack.

Pronunciation

roof jack

/ˈruːf dʒak//ˈrʊf dʒak/