The most common and most likely answer to this crossword clue is the 7 letter word NOTABLY
I've seen this crossword clue in The Guardian
N
O
T
A
B
L
Y
More clues leading to the result NOTABLY
Buddy explains!

The straight part
We know that "Particularly" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case particularly = notably.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 NOTABLY mean?
NOTABLY adverb- (focus) As a pointed example; in a notable manner.