Sun
Warmth, life and constancy — the sun runs through naming everywhere.
The Indo-European word for the sun is one of the family's best-preserved: Latin sōl, Greek hḗlios, Sanskrit sū́rya, Welsh haul and English sun all descend from it. Names built on these are ancient in every branch.
What differs is the sun's gender and temperament. In Sanskrit and Greek the sun is male and the moon is variable; in the Germanic languages the sun is grammatically feminine and the moon masculine, which is the reverse of the Romance arrangement and produces a noticeably different naming pattern. Japanese Amaterasu, the sun goddess from whom the imperial line was traditionally held to descend, is female, and sun-names for daughters are correspondingly unremarkable in Japan.
Arabic shams is feminine, and gives a productive set of names across the Arab world and beyond. Turkic gün compounds much as ay does on the moon page.
In hot climates the sun is not straightforwardly a blessing, and it is worth noticing that sun-names are proportionally more common in northern traditions than in the Gulf or the Sahel — where, as the rain page shows, the wished-for weather is different.