Synonyms of severe

1. severe, terrible, wicked, intense (vs. mild): usage: intensely or extremely bad or unpleasant in degree or quality; "severe pain"; "a severe case of flu"; "a terrible cough"; "under wicked fire from the enemy's guns"; "a wicked cough"
2. hard, knockout, severe, strong (vs. weak): usage: very strong or vigorous; "strong winds"; "a hard left to the chin"; "a knockout punch"; "a severe blow"
3. austere, severe, stark, stern, plain (vs. fancy): usage: severely simple; "a stark interior"
4. severe, spartan, nonindulgent (vs. indulgent), strict: usage: unsparing and uncompromising in discipline or judgment; "a parent severe to the pitch of hostility"- H.G.Wells; "a hefty six-footer with a rather severe mien"; "a strict disciplinarian"; "a Spartan upbringing"
5. dangerous, grave, grievous, serious, severe, life-threatening, critical (vs. noncritical): usage: causing fear or anxiety by threatening great harm; "a dangerous operation"; "a grave situation"; "a grave illness"; "grievous bodily harm"; "a serious wound"; "a serious turn of events"; "a severe case of pneumonia"; "a life-threatening disease"
6. severe, bad (vs. good): usage: very bad in degree or extent; "a severe worldwide depression"; "the house suffered severe damage"