A grammatical upheaval is turning upside down the Japanese philological grammatical tradition, rooted in the study of literature of the VIIIth-XIIth centuries, with the introduction of the Dutch Grammar during the XVIIIth century. This paper intends to highlight the grammatical hybridising process that gave rise to the modern grammatical categories, through the genetic study of two terms zidôsi/tadôsi. We will see how this pair of terms emerged from crossing the native dichotomy zi/ta with the transitive/intransitive verbs classification in European grammars.