1. Characterized by effort to the point of exhaustion; especially physical effort
   "a gruelling campaign"
   - arduous, backbreaking, grueling [US], hard, heavy, laborious, operose, punishing, toilsome

See also: effortful

• reconnoitring
• reconquer
• reconquest
• reconsecrate
• reconsecration
• reconsider
• reconsideration
• reconsolidate
• reconstitute
• reconstitution
• reconstruct
• reconstructed
• reconstruction
• Reconstruction Period
• reconstructive
• reconstructive memory
• reconstructive surgery
• reconvene
• reconversion
• reconvert
• reconvey
• reconveyance
• reconvict
• recopy
• perturbable