In Indo-European languages, the neuter is often characterized by syncretism between nominative and accusative.
There are other examples of syncretism and also historical change where the nominative pairs with accusative and genitive pairs with dative.
Is there a single name referring to something being nominative OR accusative without a further distinction being made? (Or put another way, not genitive/dative?)
Or put yet another way, if I were tagging a neuter word and wanted to indicate that the case is either nominative or accusative, is there a term for that (other than just saying nom/acc or something)?
If the four cases nominative, accusative, genitive, dative were to be treated as having a relationship:
X
+---+--- Y
| +--- nominative
| |
| +--- accusative
|
+--- Z
+--- genitive
|
+--- dative
is there a name for Y (or Z for that matter)?
EDIT: note that I'm particularly interested in labeling the morphological reflex, not the grammatical relation. In other words, I'm not attempting to make any claims about case semantics by this analysis.