Where does “lacūna” come from?
lacūna (Latin) comes from Latin lacus, from New Latin lacrimalis, from Latin lācrima, from Old Latin dacrima, from Proto-Italic *d(r)(k)akrunā, from Proto-Indo-European dáḱru-, from Proto-Indo-European dr̥ḱ-h₂eḱru- — eye bitter.
Ancestry of “lacūna”, step by step