Definition of meridian passage in US English:

meridian passage

noun

Astronomy
  • 1The passage of a celestial object across an observer's meridian.

  • 2(In full "central meridian passage") the transit of a celestial object (especially a satellite) or a surface feature across the central meridian of one of the superior planets or the sun.

Origin

Late 18th century; earliest use found in Philosophical Transactions of the Royal Society of London.