diathermanous

adj

1. (not-comparable)Having the property of transmitting radiant heat; diathermal.

   “Substances which admit of radiation taking place through them are called Diathermanous. Those which do not allow heat to pass through them without becoming themselves hot are called Athermanous. ...If the body is not perfectly diathermanous it stops more or less of the radiation, and becomes heated... instead of transmitting the whole radiation to bodies beyond it.”