The most common and most likely answer to this crossword clue is the 7 letter word VACCINE
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More clues leading to the result VACCINE
- Medical precaution: climber swallows a small quantity
- Short holiday viewed as sound, healthy preparation
- A measure of fluid injected into vein, possibly
- Inoculant needs a small volume injected into climber
- Short holiday viewed as sound, healthy preparation?
- Immunising agent that vice can ruin
- Protective preparation made by civil engineer guarding home when on holiday
- Protection against a cold reportedly identified
- Creeper placed around a small quantity of a medical breakthrough
- It provides immunity for accountant sneaking into plant
Buddy explains!

The straight part
We know that "Protection" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case protection = vaccine.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 VACCINE mean?
VACCINE noun- A substance given to stimulate the body's production of antibodies and provide immunity against a disease without causing the disease itself in the treatment, prepared from the agent that causes the disease (or a related, also effective, but safer disease), or a synthetic substitute.