pyk·nic I. adjective alsopyc·nic\ˈpiknik\ Etymology: International Scientific Vocabulary pykn-, pycn- pycn- + -ic; originally formed as German pyknisch : characterized by shortness of stature, broadness of girth, and powerful muscularity : endomorphic — compare asthenic, athletic II. noun alsopycnic\“\ (-s) : a person of pyknic build