protohuman adjective 1noun 1forms 3 adjective1 •Pertaining to the first humans or the beginning of humankind.We each had limited knowledge of forager and protohuman warfare based on either ethnographic accounts or archaeological information, which forced both of us ... — 2003 noun1 •One of the earliest humans preceding Homo sapiens.The research included an examination of the original fossils and a comparison with skeletons of modern humans and protohumans and also chimpanzees. — 2008 formsprotohumans · more protohuman · most protohuman