Severe, stern, austere, ascetic mean given to or marked by strict discipline and firm restraint. Severe implies standards enforced without indulgence or laxity and may suggest harshness. See examples of severe used in a sentence.
Severe adjective (very serious) add to word list causing great pain, difficulty, damage, etc.; Severe implies adherence to rigorous standards or high principles and often suggests harshness: Severe punishments or criticisms are very strong or harsh.
This was a dreadful crime and a severe sentence is necessary. Severe generally refers to something very great or intense, such as extreme pain or weather conditions. Definition of severe adjective in oxford advanced learner's dictionary.