footwarmer
/ˈfʊtˌwɔrmər/Definitions
1. noun
A device used to warm the feet, typically an electric heating mat or pad designed to be placed near the feet.
“She sat with her footwarmer on and felt warm and cozy.”
2. noun
A warm and sheltered spot, especially for animals, where they can rest and keep warm.
“The dogs found a cozy footwarmer by the fire and settled in for the night.”