medusa

noun

me·​du·​sa mi-ˈdü-sə 

-ˈdyü-,

-zə

1

capitalized [Latin, from Greek Medousa] : a mortal Gorgon who is slain when decapitated by Perseus

2

plural medusae mi-ˈdü-ˌsē 

-ˈdyü-,

-ˌzē,

-ˌsī,

-ˌzī

also medusas [New Latin, from Latin] : the typically free-swimming, bell-shaped, usually sexually-reproducing, solitary or colonial form of a cnidarian (such as an obelia, box jellyfish, or sea nettle) in which nematocyst-studded tentacles arise and hang down from the margin of the nearly transparent, gelatinous bell see jellyfish

medusan

mi-ˈdü-sᵊn 

-ˈdyü-

-zᵊn

adjective or noun

medusoid

mi-ˈdü-ˌsȯid 

-ˈdyü-

-ˌzȯid

adjective or noun

Examples of medusa in a Sentence

Recent Examples on the Web

When first released, Marfenin’s hydrozoan medusae are immature. —Aspen Pflughoeft, Miami Herald, 28 Aug. 2025

In its medusa form, the jellyfish grows to up to 25mm in diameter, about the size of a nickel coin. —Keith Matheny, Freep.com, 6 Aug. 2025

The polyp stage is a precursor to the medusa stage, Folino-Rorem said, when jellyfish are more visible. —Maya Wilkins, Chicago Tribune, 28 Feb. 2025

Jelly Fish with a Red Cross In 2024, an international research team discovered a new species of medusa jellyfish in the Pacific Ocean. —Monica Cull, Discover Magazine, 25 Dec. 2024

Word History

First Known Use

14th century, in the meaning defined at sense 1

Rhymes for medusa

• medusae
• arethusa
• musa

Kids Definition

medusa

noun

me·​du·​sa mi-ˈd(y)ü-sə 

-zə

plural medusae -ˌsē 

-ˌzē

also medusas

: jellyfish sense 1