1 rigorous, strict, and harsh in attitude or treatment (a severe critic; severe discipline).
2 serious, critical (a severe shortage).
3 vehement or forceful (a severe storm).
4 extreme (in an unpleasant quality) (a severe winter; severe cold).
5 arduous or exacting; making great demands on energy, skill, etc. (severe competition).
6 unadorned; plain in style (severe dress).
Derivatives:
severely adv. severity n.
Etymology: F seacutevegravere or L severus
Useful english dictionary. 2012.