The American Heritage® Dictionary of the English Language: Fourth Edition. 2000.
Appendix I
Indo-European Roots
ENTRY:
dhegwh-
DEFINITION:
To burn, warm. 1. Suffixed o-grade (causative) form *dhogwh-eyo-.foment, fomite, from Latin fov, to warm, cherish, foment. 2. Suffixed basic form dhegwh-r-.tephra, from Greek tephr, ash. (Pokorny dhegh- 240.)
, to warm, cherish, foment. 2. Suffixed basic form dhegwh-r
-. tephra, from Greek tephr
h- 240.) 
