GATHA Meaning of GATHA in English /gah"teuh, -tah/ , n. Zoroastrianism.one of several groups of hymns (the Gathas) forming the oldest part of the Avesta. [ gatha-; c. Skt gatha song ] Random House Webster's Unabridged English dictionary. Полный английский словарь Вебстер - Random House . 2012