The term 'letting up' can be defined as EASING, relenting, CEASING, or ABATING. EASING is the process of gradually reducing something, such as pressure or intensity. Relenting is to become less severe or intense, often in regards to emotions. CEASING is to stop or discontinue an action or activity. ABATING is to reduce in intensity or degree. All of these terms refer to the idea of lessening something, which is the definition of the term 'letting up'.