quinquefoliate /kwin-kwi-fōˈli-āt/ adjective

(L folium leaf) with five leaflets

quinquennˈiad noun

Quinquennium

quinquennˈial adjective

1. Occurring once in five years
2. Lasting five years

A fifth anniversary or its celebration

quinquennˈially adverb

quinquennium /kwin-kwenˈi-əm/ noun (pl quinquennˈia)

(L annus year) a period of five years

quinquereme /kwinˈkwi-rēm/ noun

(L rēmus an oar) an ancient ship with five banks of oars

quinquevˈalence (or /-vāˈ/) noun

quinquevalent or quinquivalent /kwin-kwevˈə-lənt or -kwi-vāˈ/ adjective

Having a valency of five