məˈrɪdɪən n. & adj. --n. 1 a
circle passing through the celestial poles
and zenith of
any place on the earth's
surface. 2 a a circle of
constant longitude, passing through a
given place and the
terrestrial poles. b the corresponding line on a
map. 3
archaic the
point at
which a
sun or
star attains
its highest
altitude. 4 prime; full
splendour. --adj. 1 of
noon. 2 of the
period of greatest splendour,
vigour, etc. [ME f. OF meridien or L meridianus (adj.) f. meridies
midday f. medius
middle + dies day]