sex(i)-

Six.

Latin sex, six.

A sextet is a group of six people playing music or singing together; sextuplets are a set of six children born at one birth; a sexcentenary is the six-hundredth anniversary of a significant event; a sexennial is an event recurring every six years, or a period of six years; something sextuple consists of six parts or things; For sextillion, see the entry Number words. A sextant, used for taking altitudes in navigation and surveying, is so named because the measuring arc covers one-sixth of a full circle.

Related words are formed from Latin sexaginta, sixty: sexagesimal refers to reckoning by sixtieths or a number base of sixty, which survives in angular measurement and in hours and minutes; a sexagenarian is a person in his or her sixties; Sexagesima (literally ‘sixtieth day’) is the second Sunday before Lent.