heat capacity

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The ratio of the heat energy absorbed by a substance to the substance's increase in temperature.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun physics The capability of a substance to absorb heat energy; specifically, the amount of heat required to raise the temperature of one mole or gram of a substance by one degree Celsius without any change of phase