are varieties of the same word, the root being the Sanskrit pat, to fly. (We have the Sanskrit pattra, a wing or instrument for flying; Latin, petna on penna, pen; Greek, pteron; Teutonic, phathra; Anglo-Saxon, fether; our “feather.”)
⁂ Analogous examples are Tear and Larme, Nag and Equus, Wig and Peruke, Heart and CŒur, etc.
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