What does intumesce mean?
Intumesce means to swell, usually in response to heat or another physical or chemical process. The word is especially associated with materials that expand when heated, such as certain sealants, coatings, and foams. Their expansion can help create a protective layer that resists heat or flame. In technical writing, the related adjective “intumescent” is more common than the verb itself, appearing in phrases such as “intumescent material” and “intumescent fire sealant.” Although “intumesce” is formally correct and precise, most speakers would choose “swell” or “expand” in ordinary conversation. Its specialized meaning nevertheless makes it useful when describing changes in volume that accompany heating, chemical action, or the formation of a protective structure.
verbTo swell, especially as a result of heating or a chemical or physical process. It is used chiefly in technical and formal contexts.
- To swell or expand, especially when heated.
- To become enlarged or raised in appearance through swelling.
"The material intumesces when exposed to high temperatures, expanding to form a protective layer."
"The foam intumesces rapidly in the heat of the flame."
"As the fluid heated, the surface began to intumesce."
Some materials intumesce dramatically when heated, using expansion to form a fire-resistant barrier.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does intumesce come from?
The word comes from Latin intumescere, meaning “to swell,” formed from the intensive prefix in- and tumescere, itself derived from tumere, “to swell.” English acquired the word in the 17th century for the swelling of bodies and, later, for expansion caused by heat. Related English words include “tumescent,” “tumescence,” “tumefy,” and “tumefaction,” all belonging to the same family based on the Latin root associated with swelling.
Related word forms
How intumesce is actually used
This is a formal and relatively uncommon word, occurring chiefly in technical, scientific, and materials-science contexts. In general use, “swell” or “expand” is more natural.