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

See also: effortful, toilsomeness

• eager
• eager beaver
• eagerly
• eagerness
• eagle
• eagle owl
• eagle ray
• Eagle Scout
• eagle-eyed
• eaglet
• eagre
• Eames
• Eames chair
• Eamon de Valera
• ear
• ear canal
• ear doctor
• ear fungus
• ear hole
• ear specialist
• ear trumpet
• ear-like
• ear-nose-and-throat doctor
• ear-shaped
• ear-shell