- quill, quill pen - pen made from a bird's feather
--1 is a kind of pen
- quill - a stiff hollow protective spine on a porcupine or hedgehog
--2 is a kind of spine
--2 is a part ofporcupine, hedgehog; hedgehog, Erinaceus europaeus, Erinaceus europeaeus - flight feather, pinion, quill, quill feather - any of the larger wing or tail feathers of a bird
--3 is a kind of feather, plume, plumage
--3 is a part of wing
--3 has particulars: primary, primary feather, primary quill; tail feather- quill, calamus, shaft - the hollow shaft of a feather
--4 is a kind of rib
--4 is a part of feather, plume, plumage - flight feather, pinion, quill, quill feather - any of the larger wing or tail feathers of a bird