Hemera (Ἡμέρα) is the Greek word for "day." The primordial Greek goddess of daylight — daughter of Erebus (darkness) and Nyx (night), sister of Aether (upper air).
Featured in Hesiod's Theogony.
Hemera does not currently appear in the US Social Security Administration's top 1,000 girls' names, so we don't publish a US rank or birth count for it. That says nothing about the name's standing elsewhere in the world — only that it sits outside the ranked US data we rely on.
In Pythagorean numerology the letters of Hemera reduce to 5, The Seeker. This is a traditional interpretive system, not a factual claim about the name.