A molecule is a tiny, microscopic particle made up of two or more atoms stuck together. It is the building block of all matter and can be found in things like air, water, and even your body. Full definition
At any given wavelength, the amount of light surviving goes down like the exponential of the number of molecules of CO2 encountered by the beam of light. (realclimate.org)
For weather systems, this ordinarily takes the form of heat energy trapped in water molecules in the atmosphere. (scientificamerican.com)
Food and drink must be changed into smaller molecules of nutrients before the blood absorbs them and carries them to cells throughout the body. (positivevitality.ie)