The most common and most likely answer to this crossword clue is the 7 letter word FIDGETY
F
I
D
G
E
T
Y
More clues leading to the result FIDGETY
Buddy explains!

The straight part
We know that "nervous" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case nervous = fidgety.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 FIDGETY mean?
FIDGETY adjective- Having, or pertaining to, a tendency to fidget; restless.