sisyphian
/ˌsɪsɪˈfaɪən/Definitions
1. adjective
relating to or resembling Sisyphus, who in Greek mythology was condemned to roll a heavy stone up a hill, only to have it roll back each time, repeating the task endlessly.
“The sisyphian task of cleaning the house every day seemed never-ending.”
2. noun
a task or burden that is endless and repetitive, much like Sisyphus’s labor.
“His job was a sisyphian assignment, as he had to deal with the same customer complaints daily.”