top dead centre

Definitions

Aviation

  • noun
    (written as top-dead-centre)
    the position of the piston at the extreme top of its stroke in a piston engine

Cars & Driving

  • noun the position when the piston has reached the upper limit of its travel in the cylinder and the centre line of the connecting rod is parallel to the cylinder walls.
  • acronymATDC
  • acronymBTDC
  • acronymTDC
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