The most common and most likely answer to this crossword clue is the 7 letter word SHRILLY
S
H
R
I
L
L
Y
More clues leading to the result SHRILLY
Buddy explains!

The straight part
We know that "with a sharp manner" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case with a sharp manner = shrilly.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 SHRILLY mean?
SHRILLY adverb- In a shrill manner.
- Somewhat shrill.