From protofeather + -ed or proto- + feathered. <span class="searchmatch">protofeathered</span> (not comparable) Having protofeathers....
feathered oof-bird fine-feathered friend nonfeathered pinfeathered <span class="searchmatch">protofeathered</span> unfeathered covered with feathers feathered simple past and past participle...
protoethical protoeukaryote protofascism protofascist protofeather <span class="searchmatch">protofeathered</span> protofeminism protofeminist protofeudalism protofiber protofibril protofibrillar...