variants or less commonly Ras Algethi
: 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


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

Time Traveler
The first known use of Rasalgethi was in 1780

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Dictionary Entries Near Rasalgethi

Cite this Entry

“Rasalgethi.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Rasalgethi. Accessed 10 Dec. 2023.

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