Meaning of bissextile

bis•sex•tile

Pronunciation: (bī-seks'til, -tīl, bi-), [key]
— adj.
  1. containing or noting the extra day of leap year: The years 1980 and 1984 were both bissextile.
—n.
  1. See
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.