What does lessen mean?
Lessen means to make something smaller, less severe, or less intense, or to become so in the course of time. It is especially common in formal and technical contexts involving risk, impact, pain, pressure, damage, and other conditions that can be reduced without disappearing altogether. For example, a safety measure may lessen the danger posed by a particular activity, while symptoms or conflict may lessen as the situation improves. The word is related in meaning to reduce, diminish, and mitigate, although lessen is often more strongly associated with moderation and the easing of severity. It can be used transitively, as in 'lessen the risk,' or intransitively, as when a problem 'gradually lessens.' Though standard in general English, it sounds more formal than the plainer alternatives, and 'reduce' is often the most natural choice when discussing a numerical or measurable decrease.
To reduce the size, degree, severity, or intensity of something.
"The new barriers are intended to lessen the risk of flooding."
Commonly transitive, taking the thing being reduced as its object.
To become reduced in degree, severity, or intensity.
"The pain lessened gradually over the following week."
This intransitive use is especially natural for conditions, symptoms, conflicts, and other situations that can gradually improve.
Lessen is more than making something smaller: it often means taking away severity, danger, or intensity without necessarily reducing the thing to nothing.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does lessen come from?
Lessen developed in Middle English from Old English lecsnian, a verb meaning to diminish or become less. The English word belongs to a Germanic word family associated with the comparative idea represented by less and lesser. Its modern sense developed from the older general idea of diminishing into its established use for reducing severity, intensity, risk, or effect.
Related word forms
How lessen is actually used
Lessen is formal but widely used. In formal and technical writing, it often describes a reduction in severity, risk, impact, or degree. In everyday use, people may say that something 'lessens' when they mean simply that it decreases, although 'reduce' or 'decrease' is often more direct.