a. and sb. [ad. L. bi(s)sextilis (annus), i.e., (the year) of the bissextus: see prec.]
A. adj. Containing the bissextus or extra day which the Julian calendar inserts in leap-year. Bissextile day (= L. bissextus dies; see above).
[1398. The yere Bisextilis (see prec.).]
1594. Blundevil, Exerc., III. I. xli. (ed. 7), 355. The Bissextile or leape yeere, containing 366 daies.
1696. Whiston, Th. Earth, II. (1722), 158. The Julian Calendar … intercalates the Bissextile Day immediately after the Terminalia.
1768. Blackstone, Comm., II. 140. In bissextile or leap-years.
1854. Tomlinson, Arago’s Astron., 189. Thus 1600 was bissextile, 1700 and 1800 were not so.
B. sb. Leap-year.
1581. Lambarde, Eiren., IV. v. (1588), 491. The Bissextile (or Leepe yeere) which hapneth once in every foure yeeres.
1601. Holland, Pliny, I. 586. There was no Bissextile or leap yere by him inserted, but after 12 yeres.
1834. Mrs. Somerville, Connex. Phys. Sc., xii. 95. If in addition to this, a bissextile be suppressed every 4000 years, the length of the year will be nearly equal to that given by observation.
