As titled. They seem to be made up of the same two components: 羊 and 君. As such, are they interchangeable? Or do they have different usage regardless?
Interestingly, 羣 appears to have been the "correct" version in the past, and at some point 群 took that place:
- There is a Three Kingdoms politician by the name of 陳羣, whereas the identically named Republican politician 陳群, use different characters in the last name.
- The Kangxi dictionary entry for 群 states that it is a "vulgar variant" (《五經文字》羣，俗作群。), so the transition was at least between Qing and Republic of China.
This is 异体字(variant Chinese character).
Their meaning and pronunciation are same, only different in shape.
In this case,
群 is most orthodox and known as orthodox characters(
羣 is the