Quick answer
Atalanta is a girl name meaning "equal in weight".
Meaning and history
This name comes from the Greek Ἀταλάντη (Atalante) meaning "equal in weight", derived from ἀτάλαντος (atalantos), a word related to τάλαντον (talanton) meaning "a scale, a balance". In Greek legend she was a fast-footed maiden who refused to marry anyone who could not beat her in a race. She was eventually defeated by Hippomenes, who dropped three golden apples during the race causing her to stop to pick them up.
Notes and context
Usage: greek mythology | Ancient Greek: Ἀταλάντη