Alethea ranked #4723 among U.S. baby names in 2024. Since 1892, 4,913 babies have been named Alethea, peaking in 1973 with 322 births. The 1970s were its biggest decade, with 1,215 births. Alethea is on the rise, up about 83% over the past five years. It is predominantly a girls' name.