spread-eagle (n.)

literally "splayed eagle," 1560s, a heraldic term, from past-participle adjective of spread (v.). Common on signs, flags, etc; the colloquial term was from split crow. The figure is on the seal of the United States (hence spreadeagleism "extravagant laudation of the U.S.," 1858). Meaning "person secured with arms and legs stretched out" (originally to be flogged) is attested from 1785.