1. By means of heat from the interior of the earth

See also: geothermal

• pertinency
• pertinent
• pertinently
• pertly
• pertness
• perturb
• strong-growing
• strong-minded
• strong-scented
• strong-smelling
• strong-willed
• strongbox
• stronghold
• strongly
• strongman
• strongroom
• Strongylodon
• Strongylodon macrobotrys
• strontia
• strontianite
• strontium
• strontium 90
• strop
• strophanthin
• strophanthus