/peng"gwin, pen"-/ , n. Ornith.
1. any of several flightless, aquatic birds of the family Spheniscidae, of the Southern Hemisphere, having webbed feet and wings reduced to flippers.
2. Obs. See great auk .
[ 1570-80; orig. uncert.; perh. pen gwyn lit., white head (referring to the great auk in its winter plumage); later misapplied to the Spheniscidae ]