"Guarantee/Guarantor" is the label some glossaries use for a single underlying concept covered on this wiki under Guarantor. A guarantee is the written promise, and a guarantor is the person or company making that promise, to repay a loan, rent, or other financial obligation if the primary borrower or tenant fails to do so themselves.
Rather than duplicate the explanation across two separate pages, the full discussion of how guarantees work, why lenders and landlords require them, how a guarantor differs from a co-signer, the risks a guarantor takes on, and how a guarantor can sometimes be released from the obligation, is covered on the main Guarantor entry.
In short: if a source refers to "guarantee/guarantor," it is describing exactly the same arrangement as the Guarantor entry, just phrased to name both the promise (the guarantee) and the person making it (the guarantor) together in a single term.
This short page intentionally stays brief, pointing readers to the full Guarantor entry rather than duplicating its content here.