Hycean

//ˈhaɪʃən// adj

adj ·Rare ·Advanced level

Definitions

Adjective
  1. 1
    Having a water-based ocean that covers the entire planet, and an atmosphere rich in hydrogen. neologism, not-comparable

    "With densities between those of rocky super-Earths and more extended mini-Neptunes, Hycean planets can be optimal candidates in the search for exoplanetary habitability and may be abundant in the exoplanet population."

Example

More examples

"With densities between those of rocky super-Earths and more extended mini-Neptunes, Hycean planets can be optimal candidates in the search for exoplanetary habitability and may be abundant in the exoplanet population."

Etymology

Blend of hydrogen + ocean. Coined in 2021.

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.