The most common and most likely answer to this crossword clue is the 8 letter word TREFOILS
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More clues leading to the result TREFOILS
Buddy explains!
The straight part
We know that "heraldic devices" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case heraldic devices = trefoils.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 TREFOILS mean?
TREFOILS noun- Any of several plants of the pea family, having compound, trifoliate leaves; especially one of the genus Trifolium.
- A symbol having the shape of such leaves, especially when used as an architectural ornament.
- A knot formed by joining the two loose ends of a overhand knot to form a knotted loop; the simplest non-trivial knot.