fur·nace 
(fûrnĭs)
(fûrnĭs)n.
1. An enclosure in which energy in a nonthermal form is converted to heat, especially such an enclosure in which heat is generated by the combustion of a suitable fuel.
2. An intensely hot place: the furnace of the sun; an attic room that is a furnace in the summer.
3. A severe test or trial: endured the furnace of his friends' blame after the accident.
[Middle English fourneyse, from Old French fornaise, variant of earlier fornais, from Latin fornāx, fornāc-, oven; see gwher- in the Appendix of Indo-European roots.]
- Indo-European root: preus-
- Indo-European root: prī-
- Indo-European root: pā-
- Indo-European root: pāl-
- Indo-European root: pē(i)-
- Indo-European root: pō(i)-
- Indo-European root: pū̆-
- Indo-European root: pəter-
- Indo-European root: re-
- Indo-European root: reg-
- Indo-European root: rei-
- Indo-European root: reidh-
- Indo-European root: reig-
- Indo-European root: rep-
- Indo-European root: ret-
- Indo-European root: reudh-
- Indo-European root: reug-
- Indo-European root: reup-
- Indo-European root: reuə-
- Indo-European root: rē-
- Indo-European root: rēd-
- Indo-European root: r̥tko-
- Indo-European root: sak-
- Indo-European root: sal-
- Indo-European root: sed-