Obs. [L. acies edge, keenness, sharpness.] The keen attention or aim, of the eye, ear, etc., when fully directed towards any object.
1646. Sir T. Browne, Pseud. Ep., 181. A Frogge … seemes to behold a large part of the heavens, and the acies of his eye to ascend as high as the Tropick.
1677. Hale, Prim. Orig. Man., 30. Though I do by the Empire of my Will direct the Motion or Acies of my Organ to this or that Object.
