grade, rank, class, level

rank / (school) a class / (typography) a unit equal to 1 H (ha) and 0.25 mm, abbreviated as Q, which happens to be the initial of English quarter; Q is used for font size, while ha is used for spacing

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

(slang) adult fans of an anime, a manga aimed at children

Japan

(archaic) Japan

Short for 日本国 (Nihon-koku): Japan (a country and archipelago in East Asia) / a surname

a male given name

maximize

maximization