The Collaborative International Dictionary of English v.0.48:

Spread \Spread\,
   imp. & p. p. of Spread, v.
   [1913 Webster]

   Spread eagle.
   (a) An eagle with outspread wings, the national emblem of the
       United States.
   (b) The figure of an eagle, with its wings elevated and its
       legs extended; often met as a device upon military
       ornaments, and the like.
   (c) (Her.) An eagle displayed; an eagle with the wings and
       legs extended on each side of the body, as in the
       double-headed eagle of Austria and Russia. See
       Displayed, 2.
       [1913 Webster]

WordNet (r) 3.0 (2006):

spread eagle
    n 1: an emblem (an eagle with wings and legs spread) on the
         obverse of the Great Seal of the United States
    2: a skating figure executed with the skates heel to heel in a
       straight line

Moby Thesaurus II by Grady Ward, 1.0:

193 Moby Thesaurus words for "spread eagle":
   Hershey bar, achievement, alerion, animal charge, annulet, argent,
   armorial bearings, armory, arms, aviation badge, azure, badge,
   bandeau, bar, bar sinister, baton, bearings, bend, bend sinister,
   billet, blazon, blazonry, blow down, blow over, bordure, bowl down,
   bowl over, bring down, broad arrow, bulldog, cadency mark, canton,
   capsize, careen, cast down, chaplet, charge, chevron, chicken,
   chief, chop down, coat of arms, cockatrice, come a cropper,
   coronet, crescent, crest, cross, cross moline, crown, cut down,
   dash down, deck, device, difference, differencing, down, drape,
   drop, eagle, epaulet, ermine, ermines, erminites, erminois,
   escutcheon, falcon, fall, fall down, fall flat, fall headlong,
   fall over, fall prostrate, fell, fess, fess point, fetch down,
   field, file, flanch, fleur-de-lis, floor, flounder, fret, fur,
   fusil, garland, get a cropper, griffin, ground, gules, gyron,
   hash mark, hatchment, helmet, heraldic device, hew down,
   honor point, impalement, impaling, inescutcheon,
   insignia of branch, knock down, label, lay level, lay low, lay out,
   level, lion, list, lozenge, lurch, mantling, marshaling, martlet,
   mascle, metal, motto, mow down, mullet, nombril point, oak leaf,
   octofoil, or, ordinary, organization insignia, orle, overseas bar,
   pale, paly, parachute badge, patch, pean, pheon, pip, pitch,
   precipitate, prostrate, pull down, purpure, quarter, quartering,
   ramble, rase, raze, rose, sable, saltire, scramble, scutcheon,
   send headlong, service stripe, shield, shoulder patch,
   shoulder sleeve insignia, spraddle, sprangle, sprawl, stagger,
   star, straddle, straggle, stripe, stumble, submarine badge,
   subordinary, supinate, take a fall, take a flop, take a header,
   take a pratfall, take a spill, take down, tenne, throw, throw down,
   tilt, tincture, topple, topple down, topple over, torse, totter,
   tressure, trip, tumble, turn turtle, unicorn, vair, vert,
   whack down, wreath, yale