The most common and most likely answer to this crossword clue is the 7 letter word SECURES
I've seen this crossword clue in The Daily Telegraph
S
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More clues leading to the result SECURES
Buddy explains!
The straight part
We know that "Guarantees" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case guarantees = secures.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 SECURES mean?
SECURES verb- To make safe; to relieve from apprehensions of, or exposure to, danger; to guard; to protect.
- To put beyond hazard of losing or of not receiving; to make certain; to assure; frequently with against or from, or formerly with of.
- To make fast; to close or confine effectually; to render incapable of getting loose or escaping.
- To get possession of; to make oneself secure of; to acquire certainly.
- To plight or pledge.