n. The release of previously absorbed radiation upon being heated.
the GNU version of the Collaborative International Dictionary of English
n. Luminescence exhibited by a substance on being moderately heated. It is shown esp. by certain substances that have been exposed to the action of light or to X-rays.
The Century Dictionary and Cyclopedia
n. Luminescence produced by heating a body which exhibits phosphorescence.
Word Usage
"The debate focuses on the dating technique, known as thermoluminescence (TL), which uses quartz or feldspar, ubiquitous at archaeological sites, as its subject material."