the plane passing through the spiral arms of the Galaxy
galactic plane in American English
noun
Astronomy
the plane of the galactic equator
Word origin
[1840–50]This word is first recorded in the period 1840–50. Other words that entered Englishat around the same time include: bypass, flan, organizer, pylon, striation
Examples of 'galactic plane' in a sentence
galactic plane
Its orbit is not completely flat; instead, we wiggle up and down, oscillating above and below the galactic plane, once every 35m years or so.