secondary

second party, after-party

a quadratic equation

derivative work

(Internet) redistribution

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

中々: very, quite, considerably, rather, by no means (with negative verb)

very, quite, considerably, rather / by no means (with negative verb)

the daytime, during the day / a half day, half of a day

inside