The most common and most likely answer to this crossword clue is the 5 letter word CELOM
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More clues leading to the result CELOM
Buddy explains!
The straight part
We know that "inside of American guts to a degree" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case inside of american guts to a degree = celom.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 CELOM mean?
CELOM noun- A fluid-filled cavity within the body of an animal. The digestive system is suspended within the cavity, which is lined by a tissue called the peritoneum.