What does the cryptic crossword clue "Girl endlessly radiant after somersault (4)" mean?

The definition is "Girl". The wordplay uses a reversal. AGLO (reversal="AGLO") = OLGA; definition: "Girl" The answer is OLGA.

Girl endlessly radiant after somersault (4)

Guardian Cryptic #29311 | 22 Across | 2024-02-21 flower