Below are possible answers for the crossword clue Requiring much time and effort.
9 letter answer(s) to requiring much time and effort
LABORIOUS
characterized by effort to the point of exhaustion; especially physical effort; "worked their arduous way up the mining valley"; "a grueling campaign"; "hard labor"; "heavy work"; "heavy going"; "spent many laborious hours on the project"; "set a punishing pace"
difficult
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