一際[hitokiwa] conspicuously
学際的[gakusaiteki] interdisciplinary
真際[magiwa] on the verge of
金輪際[konrinzai] the deepest bottom of the earth
交際[kousai] company

交際家[kousaika] sociable person
交際嫌い[kousaigirai] unsociable
交際好き[kousaizuki] sociable
交際国[kousaikoku] friendly powers
交際社会[kousaishakai] society