The opening and closing may be connected by four distinct relations. Their names should not be treated as interchangeable.
TypeDiagnostic feature
RepetitionThe same identifiable expression returns
JināsTwo expressions resemble each other in sound or form
DerivationBoth forms genuinely derive from one root
Quasi-derivationThey resemble derivatives without a demonstrated common root
Sound is relevant, but derivational history and context decide the precise category.