1651, said to have been applied to them in 1650 by Justice Bennett at Derby, from George Fox's admonition to his followers to "tremble at the Word of the Lord;" but the word was used earlier of foreign sects given to fits of shaking during religious fervor, and that is likely the source here. Either way, it was never an official name of the Religious Society of Friends. Quaker gun (1809, Amer.Eng.) was a log painted black and propped up to look from a distance like a cannon.
1906, named for U.S. president Theodore "Teddy" Roosevelt, a noted big-game hunter, whose conservationist fervor inspired a comic illustrated poem in the "New York Times" of Jan. 7, 1906, about two bears named Teddy, whose names were transferred to two bears presented to the Bronx Zoo that year. The name was picked up by toy dealers in 1907 for a line of "Roosevelt bears" imported from Germany. Meaning "big, lovable person" first attested 1957, from the song popularized by Elvis Presley.
c.1600, from M.Fr. enthousiasme, from Gk. enthousiasmos, from enthousiazein "be inspired," from entheos "inspired, possessed by a god," from en- "in" + theos "god" (see Thea). Acquired a derogatory sense of "excessive religious emotion" (1650s) under the Puritans; generalized sense of "fervor, zeal" (the main modern sense) is first recorded 1716.