The most common and most likely answer to this crossword clue is the 8 letter word CYANIDES
C
Y
A
N
I
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S
Buddy explains!
The straight part
We know that "compounds containing carbon and nitrogen" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case compounds containing carbon and nitrogen = cyanides.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 CYANIDES mean?
CYANIDES noun- Any compound containing the -C≡N radical or the C≡N-1 anion.
- Potassium cyanide - a water soluble poison
- Hydrogen cyanide, or cyanide gas - a poisonous gas