British thermal unit: a unit of heat equal to the amount of heat required to raise one pound of water one degree Fahrenheit at one atmosphere
Related Amounts:
1 Watt = 3.413 BTU*
1 Gallon Propane = 91,330 BTU*
1 Gallon Fuel Oil (#2) = 138,690 BTU*
1 Therm (of any fuel) = 100,000 BTU*
1 Ton = 12,000 BTU*
*(US Dept of Energy)
