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Heliacal

/hɪˈlaɪəkəl/adjective

Describing a star's first reappearance at dawn after weeks lost in the sun's glare.

The Greek roots

ἥλιος
hḗlios
sun

Literally: belonging to the sun

Follow a root:ἥλιος14 words

The story of the word

Egyptian agriculture ran on one such event. The heliacal rising of Sirius announced the Nile flood, and the calendar was pinned to it. Greek ἡλιακός meant nothing more elaborate than belonging to the sun, and the same ἥλιος named the element helium after it was found in the sun's spectrum before anyone found it on earth.

How it travelled
Ancient Greek → Latin → English
First recorded
16th century

The same roots elsewhere

Other languages reached for exactly the same Greek pieces.

Same family

heliumheliocentricperihelionheliotrope

In a sentence

They camped in the desert to catch the heliacal rising of Sirius.

Built on the same root

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