界

the four great civilizations of the world (China, Babylon, India, and Egypt; as put forward by Chinese scholar Liang Qichao in 1900)

marginal utility

Mathematics

lower bound

utopia

world policy

watershed; divide

grain boundary

Medicine

borderline personality disorder

Roche limit; Roche's limit (closest that a natural satellite can come to the center of a planet without disintegrating due to tidal forces)

world financial crisis (2007-2008); global financial crisis; GFC

lack of boundary; borderless (psych.); confluence (psych.)

tropopause

international exposition; world expo

limit gauge; limit gage

Organization name

World Federation of Trade Unions; WFTU

Buddhism

world of the lost; human realm; this world

the world of sports

medical world

Abbreviation

world expo; world fair

world recession

global recession

closed world

Organization name

Unification Church (kor: Tongil Gyohoe); The Holy Spirit Association for the Unification of World Christianity

Biology

umwelt; self-centered world