攸关 (攸關) yōuguān

yōuguān verb to be of great concern
Domain: Modern Chinese 现代汉语
Notes: (ABC 'yōuguān'; NCCED '攸') 生死攸关 'to be of concern to life and death.' (VOA 2016-01-24)

Also contained in

生死攸关 、 存亡攸关 、 利害攸关 、 性命攸关