Where does “cuna” come from?

cuna (Old Portuguese) comes from Vulgar Latin cunea, from Latin cuneus, from Proto-Indo-European h₂ḱū, from Proto-Indo-European h₂eḱ- — sharp.

Ancestry of “cuna”, step by step

StepLanguageWordMeaning
1Vulgar Latincuneasecond-person singular present active imperative...
2Latincuneuswedge, wedge shape; troops arrayed in a wedge...
3Proto-Indo-Europeanh₂ḱūsting
4Proto-Indo-Europeanh₂eḱ-sharp
Every word from Proto-Indo-European h₂eḱ- →Every word from Proto-Indo-European h₂ḱū →Every word from Latin cuneus →