grueling

[ groo-uh-ling, groo-ling ]
/ ˈgru ə lɪŋ, ˈgru lɪŋ /

adjective

exhausting; very tiring; arduously severe: the grueling Boston marathon.

noun

any trying or exhausting procedure or experience.
Also especially British, gru·el·ling.

Origin of grueling

1850–55; slang gruel punishment (noun), punish (v.) + -ing2, -ing1

Related forms

gru·el·ing·ly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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