thermodynamics
n. uncountablen. the branch of science that studies how heat and energy move and change into different forms. It explains how things like engines and refrigerators work.
n. the branch of physical science dealing with the relations between heat and other forms of energy. It describes how thermal energy is converted to and from other forms of energy and how it affects matter.
The laws of thermodynamics explain why heat moves from hot to cold.
Engineers must understand thermodynamics to design more efficient car engines that waste less fuel as heat.
The second law of thermodynamics states that the total entropy of an isolated system can never decrease over time, effectively defining the direction of physical processes.
From thermo- + dynamics. First attested in the 1850s.
Treated as a singular noun despite the 's' ending; takes a singular verb.
Thermodynamics are a difficult subject.Thermodynamics is a difficult subject.Names of sciences ending in -ics are treated as singular, not plural.