Five; having five parts.
From Latin quinque, five.
An event which is quinquennial happens once every five years (less usually, it lasts for five years); any period of five years may be called a quinquennium; a quincentenary is the five-hundredth anniversary of a significant event; a quincunx is an arrangement of five objects with four at the corners of a square and the fifth at its centre, like the five on dice. In botany something quinquefoliate has five leaves or leaflets. The related Latin word for fifty, quinquaginti, appears in quinquagenarian, a person in their fifties, and in Quinquagesima, the Sunday before the beginning of Lent, taken to be 50 days before Easter.