Lessening means making or becoming smaller in size, amount, or degree. It's like reducing something.
When we talk about lessening, it usually refers to making something smaller or decreasing its impact. For example, "The rain started to lessen" might mean that the storm was slowly going away and the sun would come out soon. We can also talk about lessening our carbon footprint by using public transport instead of driving a car every day. In this case, we're reducing our effect on the environment. Sometimes, people talk about lessening their expenses or workload to make things easier for themselves. It's all about making something smaller or more manageable.
To make less; to diminish; to reduce.
A growing lesser; reduction or decrease.
