intumescent

/ɪntuːˈmɛsənt/
adjective
  1. Tending to swell or expand when heated, often used to describe fire-resistant materials.
    • Builders use intumescent seals around doors to stop smoke from spreading.
    • This intumescent coating can withstand high temperatures for hours.
    • The intumescent paint swells to protect the wall from fire.
  2. Swollen or enlarged in form.
    • The intumescent tissue around the wound indicated healing.
    • An intumescent growth appeared on the old oak tree.
    • The intumescent leaves of the succulent store water.
Synonyms
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