needing and using much energy and thought

difficult, hard to endure

of, for, discipline

corrective

(of pain, suffering, bodily or mental) extreme

torturous, painful

exhausting

difficult, taxing

connected with punishment

disciplinary

(intended for) punishment; very severe

concerning punishment

(of a storm etc) (continuing) without a decrease in strength

continuous, never-ending

very (big of its kind); a beating

striking