ˌpirēəˈdisəd.ē, ˌpēr-, -sətē, -i noun
( -es )
Etymology: French périodicité, from Latin periodicus + French -ité -ity
: the quality, state, or fact of being regularly recurrent: as
a. : the tendency of a plant to exhibit rhythmical changes in such vital functions as nyctitropic movements, root pressure, flowering, and fruiting
b. : the position of an element in the periodic table
c. : electrical frequency