The most common and most likely answer to this crossword clue is the 8 letter word HARDSHIP
I've seen this crossword clue in The Daily Telegraph
H
A
R
D
S
H
I
P
More clues leading to the result HARDSHIP
- Owned vessel crossing river for trial
- Certainly no inflatable in difficulty
- Novelist draining last short drink round hotel has difficulty
- Is obliged to cross road in difficulty
- Need solid vessel
- Difficulty encountered in powerful vessel
- Rigorous internet protocol limiting daughter’s misfortune
- Severity of mess around road — I start to protest
- Rigid boat in difficulty
- Stern in front of vessel? That’s difficult to take
Buddy explains!

The straight part
We know that "Severity" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case severity = hardship.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does HARDSHIP mean?
HARDSHIP noun- Difficulty or trouble; hard times.
- To treat (a person) badly; to subject to hardships.