My first definition of chemistry is the study of chemicals (that's how I remember it) and how they react with each other and how to describe the experience and experiments in the most precise and concise words to be interpreted by other people in the scientific community and hopefully the non-scientific community.
My second definition of chemistry is from pop culture, which seems to mean how people relate to each other. A higher chemistry means people get along with each other well. A lower chemistry means people get along poorly or disagree most of the time.
NOTE: This example tries to combine both definitions to get a shared meaning.
Example: The chemicals are having a good chemistry with each other and reacting to beget inorganic or organic products. Sodium hydroxide and hydrochloric acid have excellent chemistry and marry and form their children called sodium chloride and dihydrogen monoxide (commonly known as water by its common name). At the atomic level, the ions are chemically bonding tightly! Yep, it's a real close lovely relationship!
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