counter for number of kinds or types

an origin, cause / a type, class / an interest, appeal

a seed / a kind, type, sort, class, or category / (taxonomy) a species

world / a metaphorical world (how one lives one's life) / society, the times / a realm, a circle, a sphere / (Buddhism) the four inner realms of 須弥山 (Shumisen) / (Buddhism) realm governed by a buddha

one day

maximization

maximize

maximum

one, 1 / the first in order, foremost / the beginning / the best / a kind of; one of something / (card games) an ace / unity / the bottom string of a shamisen or other Japanese musical instrument

each person