Eileithyia (or Ilithyia) was the Greek goddess of childbirth whose Roman equivalent was Lucina (later Diana). As befits her speciality, her name means 'she who comes (to help)', from elelytha, 'she has come', since she came to the aid of women in labour.

However, the 'light' meanings of her Roman names also suggests a possible derivation from hele, 'sunlight' and thyo, 'to move rapidly'. In the Knossos Linear Β tablets her name appears as Eleuthia, which in turn suggests eleutheria, 'freedom', 'liberty'.