severest

adjective severer, severest

1. harsh, strict, or highly critical, as in treatment; unsparing; stern
2. serious or grave; forbidding, as in expression or manner
3. serious or grievous: a severe wound
4. conforming strictly to a rule, method, standard, etc.; rigidly accurate or demanding: a severe philosophy
5. extremely plain or simple; unornamented; restrained: a dress with severe lines
6. keen; extreme; intense: severe pain
7. difficult; rigorous; trying: a severe test