Word.ws English Dictionary

space jellyfish

space jellyfish noun: an atmospheric phenomenon of the early morning or late evening, where the ground is in nighttime, but sunlight shines through the upper atmosphere, whereby rocket exhaust, the rocket plume, expanding in the upper atmosphere reflects light, creating a visual appearance similar to that of a jellyfish. It can result in reports of UFO sightings.

space jellyfish: an atmospheric phenomenon of the early morning or late evening, where the ground is in nighttime,...
Image: Official SpaceX Photos, CC0, via Wikimedia Commons

Noun

space jellyfish (plural space jellyfishes or space jellyfish)

  1. (informal, space flight) An atmospheric phenomenon of the early morning or late evening, where the ground is in nighttime, but sunlight shines through the upper atmosphere, whereby rocket exhaust, the rocket plume, expanding in the upper atmosphere reflects light, creating a visual appearance similar to that of a jellyfish. It can result in reports of UFO sightings.
  2. (informal, space flight) An atmospheric phenomenon of the moon-lit nighttime, whereby expanding rocket exhaust in the night sky reflects moonlight, creating the appearance similar to that of a jellyfish.

Synonyms of space jellyfish

Forms of space jellyfish

pluralspace jellyfishes
pluralspace jellyfish

Origin of space jellyfish

space + jellyfish. From having a jellyfish-like appearance, and being in the sky.

Questions about space jellyfish

What does space jellyfish mean?
Space jellyfish means an atmospheric phenomenon of the early morning or late evening, where the ground is in nighttime, but sunlight shines through the upper atmosphere, whereby rocket exhaust, the rocket plume, expanding in the upper atmosphere reflects light, creating a visual appearance similar to that of a jellyfish. It can result in reports of UFO sightings.
What part of speech is space jellyfish?
Space jellyfish is a noun.
What is the plural of space jellyfish?
The plural of space jellyfish is space jellyfishes.

Words near space jellyfish in the dictionary

  1. space hopper
  2. space hoppers
  3. space ice cream
  4. space invader
  5. space invaders
  6. space jellyfish
  7. space junk
  8. Space Karen
  9. space lattice
  10. space lattices
  11. Space Launch System

Source and license

Adapted from Wiktionary: space jellyfish (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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Cite this entry: “space jellyfish.” Word.ws, https://word.ws/space_jellyfish. Based on Wiktionary, CC BY-SA 4.0.