The most common and most likely answer to this crossword clue is the 6 letter word PLEXUS
P
L
E
X
U
S
More clues leading to the result PLEXUS
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The straight part
We know that "Network behind corporation, say" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case network behind corporation, say = plexus.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 PLEXUS mean?
PLEXUS noun- A network or interwoven mass, especially of nerves, blood vessels, or lymphatic vessels.
- The system of equations required for the complete expression of the relations which exist between a set of quantities.