Rasalgethi

noun

Ras·​al·​ge·​thi

variants or less commonly Ras Algethi

ˈräs-ˌal-jə-ˈtē,

-al-ˈge-thē

astronomy

: a group of stars of the third magnitude that is seen in the constellation Hercules

Hercules resembles the constellation Orion but only has two stars along the belt (rather than three) and is not as bright as Orion but still recognizable. In Hercules, there is an interesting double star known as Rasalgethi, located above his head.

—Chris Pagan, Tulsa World (Oklahoma), 5 June 2011

called also Alpha Herculis

Note: What is visible in the night sky as the star Rasalgethi is actually a group of three stars bound together gravitationally; one red giant and a binary system of a yellow giant and a yellow dwarf star.

Word History

Etymology

borrowed from New Latin, borrowed from Arabic ra's al-jāthī, literally, "head of the kneeling one"

First Known Use

1780, in the meaning defined above

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