‖Ly″ra (?), n. [L. lyra, Gr. �. See Lyre.] 1. (Astron.) A northern constellation, the Harp, containing a white star of the first magnitude, called Alpha Lyræ, or Vega.
2. (Anat.) The middle portion of the ventral surface of the fornix of the brain; — so called from the arrangement of the lines with which it is marked in the human brain.