( US grueling )
■ adjective extremely tiring and demanding.
Derivatives
~ly adverb
Origin
C19: from gruel 'exhaust, punish', from an old phr. get one's gruel 'receive one's punishment'.
GRUELLING
Meaning of GRUELLING in English
Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004