The most common and most likely answer to this crossword clue is the 9 letter word RESPONSES
I've seen this crossword clue in The Guardian
R
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More clues leading to the result RESPONSES
Buddy explains!
The straight part
We know that "reactions" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case reactions = responses.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 RESPONSES mean?
RESPONSES noun- An answer or reply, or something in the nature of an answer or reply.
- The act of responding or replying; reply: as, to speak in response to a question.
- An oracular answer.
- (liturgics) A verse, sentence, phrase, or word said or sung by the choir or congregation in sequence or reply to the priest or officiant.
- (liturgics) A versicle or anthem said or sung during or after a lection; a respond or responsory.
- A reply to an objection in formal disputation.
- An online advertising performance metric representing one click-through from an online ad to its destination URL.
- A reaction to a stimulus or provocation.