n. [ L. bissextilis annus, fr. bissextus (bis + sextus sixth, fr. sex six) the sixth of the calends of March, or twenty-fourth day of February, which was reckoned twice every fourth year, by the intercalation of a day. ] Leap year; every fourth year, in which a day is added to the month of February on account of the excess of the tropical year (365 d. 5 h. 48 m. 46 s.) above 365 days. But one day added every four years is equivalent to six hours each year, which is 11 m. 14 s. more than the excess of the real year. Hence, it is necessary to suppress the bissextile day at the end of every century which is not divisible by 400, while it is retained at the end of those which are divisible by 400. [ 1913 Webster ]

a. Pertaining to leap year. [ 1913 Webster ]

n. [ Prop., in sixteenth; fr. L. decimus tenth + sextus sixth. ] A book consisting of sheets, each of which is folded into sixteen leaves; hence, indicating, more or less definitely, a size of book; -- usually written 16mo or 16°. [ 1913 Webster ]

a. Having sixteen leaves to a sheet; as, a decimosexto form, book, leaf, size. [ 1913 Webster ]

n. (Astrol.) An aspect of the planets when they are distant from each other the twelfth part of a circle, or thirty degrees. Hutton. [ 1913 Webster ]

n. [ L. sexta, fem. of sextus sixtt, fr. sex six: cf. F. sexte. ] (R.C.Ch.) (a) The office for the sixth canonical hour, being a part of the Breviary. (b) The sixth book of the decretals, added by Pope Boniface VIII. [ 1913 Webster ]

n. [ L. sextus sixth, fr. sex six: cf. It. sestina. ] (Pros.) A stanza of six lines; a sestine. [ 1913 Webster ]

‖n. [ L. See Sextant. ] 1. (Rom. Antiq.) A Roman coin, the sixth part of an as. [ 1913 Webster ]

2. (Astron.) A constellation on the equator south of Leo; the Sextant. [ 1913 Webster ]

n. [ L. sextans, -antis, the sixth part of an as, fr. sextus sixth, sex six. See Six. ] 1. (Math.) The sixth part of a circle. [ 1913 Webster ]

2. An instrument for measuring angular distances between objects, -- used esp. at sea, for ascertaining the latitude and longitude. It is constructed on the same optical principle as Hadley's quadrant, but usually of metal, with a nicer graduation, telescopic sight, and its arc the sixth, and sometimes the third, part of a circle. See Quadrant. [ 1913 Webster ]

3. (Astron.) The constellation Sextans. [ 1913 Webster ]

Box sextant, a small sextant inclosed in a cylindrical case to make it more portable. [ 1913 Webster ]

n.; pl. Sextaries [ L. sextarius the sixth part of a measure, weight, etc., fr. sextus sixth, sex six. ] (Rom. Antiq.) An ancient Roman liquid and dry measure, about equal to an English pint. [ 1913 Webster ]

n. [ For sextonry. ] A sacristy. [ Obs. ] [ 1913 Webster ]

{ } n. (Mus.) See Sestet. [ 1913 Webster ]

n. A sacristan. [ Obs. ] Chaucer. [ 1913 Webster ]

a. [ L. sextus sixth. ] (Math.) Of the sixth degree or order. -- n. (Alg.) A quantic of the sixth degree. [ 1913 Webster ]

a. [ F. sextil, fr. L. sextus the sixth, from sex six. See Six. ] (Astrol.) Measured by sixty degrees; fixed or indicated by a distance of sixty degrees. Glanvill. [ 1913 Webster ]

n. [ Cf. F. aspect sextil. ] (Astrol.) The aspect or position of two planets when distant from each other sixty degrees, or two signs. This position is marked thus: ✶. Hutton. [ 1913 Webster ]

n. [ Formed (in imitation of million) fr. L. sextus sixth, sex six: cf. F. sextilion. ] According to the method of numeration (which is followed also in the United States), the number expressed by a unit with twenty-one ciphers annexed. According to the English method, a million raised to the sixth power, or the number expressed by a unit with thirty-six ciphers annexed. See Numeration. [ 1913 Webster ]

n.; pl. Sextos [ L. sextus sixth. ] A book consisting of sheets each of which is folded into six leaves. [ 1913 Webster ]

a. [ L. sextus-decimus the sixteenth; sextus the sixth (fr. sex six) + decimus the tenth, from decem ten. See -mo. ] Having sixteen leaves to a sheet; of, or equal to, the size of one fold of a sheet of printing paper when folded so as to make sixteen leaves, or thirty-two pages; as, a sextodecimo volume. [ 1913 Webster ]

n.; pl. Sextodecimos A book composed of sheets each of which is folded into sixteen leaves; hence, indicating, more or less definitely, a size of a book; -- usually written 16mo, or 16°. [ 1913 Webster ]

n. (Mus.) A double triplet; a group of six equal notes played in the time of four. [ 1913 Webster ]

n. [ OE. sextein, contr. fr. sacristan. ] An under officer of a church, whose business is to take care of the church building and the vessels, vestments, etc., belonging to the church, to attend on the officiating clergyman, and to perform other duties pertaining to the church, such as to dig graves, ring the bell, etc. [ 1913 Webster ]

Sexton beetle (Zool.), a burying beetle. [ 1913 Webster ]

n. A female sexton; a sexton's wife. [ 1913 Webster ]

n. Sextonship. [ Obs. ] Ld. Bernes. [ 1913 Webster ]

n. The office of a sexton. Swift. [ 1913 Webster ]

n. See Sacristy. [ Obs. ] [ 1913 Webster ]

a. [ Formed (in imitation of quadruple) fr. L. sextus sixth: cf. F. sextuple. ] 1. Six times as much; sixfold. [ 1913 Webster ]

2. (Mus.) Divisible by six; having six beats; as, sixtuple measure. [ 1913 Webster ]

a. Having the ratio of one to six; as, a subsextuple proportion. Bp. Wilkins. [ 1913 Webster ]