'Sisyphean' definitions:

Definition of 'Sisyphean'

(from WordNet)
adjective
Of or relating to Sisyphus
adjective
Both extremely effortful and futile

Definition of 'Sisyphean'

From: GCIDE
  • Sisyphean \Sis`y*phe"an\, a. Relating to Sisyphus; incessantly recurring; as, Sisyphean labors. [1913 Webster]