What does the cryptic crossword clue "Really minced its oaths (2,4,2)" mean?

The definition is "Really". The wordplay uses an anagram. anagram of ITS + OATHS = ISTHATSO; definition: "Really" The answer is ISTHATSO.

Really minced its oaths (2,4,2)

Guardian Cryptic #29565 | 5 Down | 2024-12-13 flower