The most common and most likely answer to this crossword clue is the 9 letter word ANTISERUM
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More clues leading to the result ANTISERUM
- Term in USA recollecting an agent of passive immunity?
- Something injected ruins meat, sadly
- Possible treatment, mixture of tisane and rum
- I’m nature’s fluid remedy for disease
- With one getting bitten, mate runs for restoring immunising agent
- Medicinal fluid: sick man rues swallowing it up
- Team is run in order to get medical substance
- Something injected ruins meat badly
- Ruminates about blood component containing antibodies
- Ruminates about vaccine
Buddy explains!

The straight part
We know that "immunising agent" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case immunising agent = antiserum.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 ANTISERUM mean?
ANTISERUM noun- A serum prepared from human or animal sources containing antibodies specific for combatting an infectious disease.