Iapetus

American  

[ahy-ap-i-tuhs, ee-ap-] / aɪˈæp ɪ təs, iˈæp- /

noun

1. Classical Mythology. a Titan, son of Uranus and Gaia.

2. Astronomy. a natural satellite of the planet Saturn.

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Iapetus British  

/ aɪˈæpɪtəs /

noun

1. a large outer satellite of the planet Saturn

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Etymology

Origin of Iapetus

First recorded in 1600–20; Latin Īapetus, from Greek Īapetós; further origin uncertain; probably from the same source as Hebrew Yepheth; Japheth ( def. )

Example Sentences

The team also found that before it disappeared, Proto-Hyperion could have tilted the orbit of Saturn's distant moon Iapetus, potentially solving another longstanding mystery about the Saturn system.

From Science Daily • Feb. 27, 2026

In the book you mention that you like Saturn’s moon Iapetus because of its different hemispheres and describe how that idea of polarity is compelling to you.

From Scientific American • Jul. 24, 2023

In simulations, the researchers included an object about the size of Iapetus, Saturn’s third largest moon, orbiting about 43 Saturn radii out—between the orbits of Titan and Iapetus.

From Science Magazine • Sep. 14, 2022

The thinning, flattening crust created a shallow rift that eventually filled with water, which geologists call the Iapetus Ocean.

From Washington Post • Jun. 3, 2021

Take away Bob’s broom and his janitor’s clothes, put him in armor and cut his hair, change his color scheme from silver to gold, and Iapetus would have been almost indistinguishable from Hyperion.

From "The House of Hades" by Rick Riordan