The most common and most likely answer to this crossword clue is the 7 letter word FERMATA
I've seen this crossword clue in The Times
F
E
R
M
A
T
A
Buddy explains!
The straight part
We know that "pause in a bar" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case pause in a bar = fermata.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 FERMATA mean?
FERMATA noun- The holding of a note or rest for longer than its usual duration; also the notation of such a prolongation, usually represented as a dot with a semi-circle above or below it, written above or below the prolonged note or rest.