As nouns,
first law of thermodynamics is a hyponym of
conservation; that is,
first law of thermodynamics is a
word with a more specific, narrower meaning than
conservation:
- conservation: (physics) the maintenance of a certain quantities unchanged during chemical reactions or physical transformations
- first law of thermodynamics: the fundamental principle of physics that the total energy of an isolated system is constant despite internal changes
Other hyponyms of conservation include
conservation of charge,
conservation of electricity,
conservation of energy,
law of conservation of energy,
conservation of mass,
conservation of matter,
law of conservation of mass,
law of conservation of matter,
conservation of momentum,
conservation of parity,
mirror symmetry,
parity,
space-reflection symmetry.