The most common and most likely answer to this crossword clue is the 7 letter word VENTRAL
V
E
N
T
R
A
L
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The straight part
We know that "On the low side" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case on the low side = ventral.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 VENTRAL mean?
VENTRAL noun- Any of the enlarged and transversely elongated scales that extend down the underside of a snake's body from the neck to the anal scale.
- Related to the abdomen or stomach.
- On the front side of the human body, or the corresponding surface of an animal, usually the lower surface.
- On or relating to the bottom portion of either foot and/or hand.