The direct case is often imprecisely called the "nominative" in South Asia and "absolutive" in the Philippines, but linguists typically reserve those terms for grammatical cases that have a narrower scope.
For example, Dixon[1] describes "proto-Pamir" as having, in the present tense, the direct case for S and A and the oblique case for O (a nominative–accusative alignment), and, in the past tense, the direct for S and O and the oblique for A (an absolutive–ergative alignment).
Because of this split (see split ergativity), neither "nominative" nor "absolutive" is an adequate description of the direct case, just as neither "accusative" nor "ergative" is an adequate description of the oblique case.
The situation in the Irish language is similar, though some pronouns retain a distinction (e.g. "you" (singular) - nominative tú, accusative thú) In languages of the Philippines, and in related languages with Austronesian alignment, the direct case is the case of the argument of an intransitive clause (S), and may be used for either argument of a transitive clause (agent or patient), depending on the voice of the verb.
This is analogous to the direct–oblique distinction in proto-Pamir, but with the split conditioned by voice rather than by tense.