Eartha is from the Old English eorþe — the earth, soil, planet. Eartha Kitt (1927-2008) — American singer, actress, and dancer; Orson Welles called her "the most exciting woman in the world". Born in South Carolina to a 14-year-old Black-Cherokee mother and an unknown father; raised in foster care in Harlem from age 8. Her sultry 1953 holiday song "Santa Baby" remains the highest-charting Black-female recording of a Christmas standard. Spoke fluent English, French, German, Spanish, Dutch, Portuguese, and conversational Chinese. Lady Bird Johnson's 1968 White House luncheon — at which Eartha publicly criticized the Vietnam War — got her blacklisted for ten years.
Subject of John Williams's Eartha & Kitt: A Daughter's Love Story (2021).
Eartha 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 Eartha reduce to 8, The Visionary. This is a traditional interpretive system, not a factual claim about the name.