The Aramaic particle דִּי is the workhorse of Biblical Aramaic syntax, functioning as relative pronoun, conjunction, genitive marker, and more — all packed into two consonants. Cognate with Hebrew אֲשֶׁר and Ethiopic ዘ (za), it descends from a demonstrative root meaning 'that one,' which grammaticalized into a general subordinator. In Daniel and Ezra, דִּי stitches nearly every complex sentence together, and its versatility challenges translators: the same particle rendered 'who' in one clause becomes 'of' in the next and 'because' in the third. Spanish que and French qui capture the relative uses but require different words (de, porque, cuando) for genitive, causal, and temporal functions that דִּי handles alone.