医界[ikai] medical world
医学界[igakukai] medical world
黄金世界[ougonsekai] utopia
下界[gekai] this world
花柳界[karyuukai] red-light district

界隈[kaiwai] neighborhood
界面[kaimen] interface
各界[kakkai] each field
学界[gakkai] academic or scientific world
官界[kankai] bureaucracy

君臨[kunrin] reigning
降臨[kourin] advent
再降臨[saikourin] Second Advent
再臨[sairin] second coming
再臨派[sairinha] Adventists

台臨[tairin] visit by the empress or the crown prince
臨く[nozoku] to peek (though a keyhole, gap, etc.)
来臨[rairin] attendance
臨む[nozomu] to look out on
臨界[rinkai] critical (pressure, temperature, state, point)