Forbearance
Contract Law

A forbearance is a failure or election not to enforce a legal right, as opposed to a variation of a contract which is legal binding. As a forbearance is not supported by consideration, it is not legally binding in most instances. Forbearances may generally be withdrawn or retracted on reasonable notice. Exceptions are likely to apply where the other party relies on the forbearance and irretrievably changes their position. 

Equity will recognise forbearances by conduct which are unsupported by consideration, where there is a legal relationship giving rise to rights and duties (for instance, between a landlord and tenant). A contract is not necessarily required.

This equitable doctrine is also known as promissory estoppel.