To save this word, you'll need to log in.
Medical Definition of law of thermodynamics
1 : conservation of energy
— called also first law of thermodynamics
2 : a law in physics: mechanical work can be derived from the heat in a body only when the body is able to communicate with another at a lower temperature or all actual spontaneous processes result in an increase of total entropy
— called also second law of thermodynamics
3 : a law in physics: at the absolute zero of temperature the entropy of any pure crystalline substance is zero and its derivative with respect to temperature is zero
— called also third law of thermodynamics
Comments on law of thermodynamics
What made you want to look up law of thermodynamics? Please tell us where you read or heard it (including the quote, if possible).
Test Your Vocabulary
Semantic Drift Quiz
- Which of the following was once a synonym for fun?
Can you spell these 10 commonly misspelled words?
TAKE THE QUIZ
Test Your Knowledge - and learn some interesting things along the way.
TAKE THE QUIZLove words? Need even more definitions?
Merriam-Webster unabridgedWords at Play
Ask the Editors
Word Games
Share law of thermodynamics