The most common and most likely answer to this crossword clue is the 6 letter word SURETY
I've seen this crossword clue in The Guardian
S
U
R
E
T
Y
More clues leading to the result SURETY
Buddy explains!
The straight part
We know that "guarantor/guarantor" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case guarantor/guarantor = surety.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 SURETY mean?
SURETY noun- Certainty.
- That which makes sure; that which confirms; ground of confidence or security.
- A promise to pay a sum of money in the event that another person fails to fulfill an obligation.
- One who undertakes to pay money or perform other acts in the event that his principal fails therein.
- A substitute; a hostage.
- Evidence; confirmation; warrant.