The most common and most likely answer to this crossword clue is the 7 letter word UNTWIST
I've seen this crossword clue in The Times
U
N
T
W
I
S
T
More clues leading to the result UNTWIST
Buddy explains!

The straight part
We know that "Straighten out" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case straighten out = untwist.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 UNTWIST mean?
UNTWIST noun- A twist in the opposite direction.
- To remove a twist from.
- To become untwisted.