ˈ ̷ ̷ˌ ̷ ̷ noun
1. : a bed of soil enclosed in a low glass frame heated by fermenting manure or by other means and used for forcing or for raising early seedlings — compare cold frame
2. : a place or environment which favors rapid growth or development
hotbed of crime
3. : a frame or area in a rolling mill on which hot bars or rails are laid to cool