ciel
n. m. 'sky'
From Classical Latin 'caelum', meaning 'sky, heaven'.
Historical Pronunciation
2000 - Modern French
[sjɛl]
1500 - Middle French
[sjɛl]
1200 - Late Old French
[tsiɛl]
900 - Early Old French
[tsiɛl]
700 - Late Gallo-Romance
[tsiɛl]
400 - Early Gallo-Romance
[tsiɛlo]
100 - Vulgar Latin
[kɛlu]
CL - Classical Latin
[kaɛlu]
Latin Root
caelum
The plural cieux is used in religious contexts, while ciels is used for artistic or meteorological contexts.