As a noun, it is the feeling of wanting to know or learn more about something, or the extra money paid for using someone else’s money. As a verb, it means to attract someone’s attention or curiosity.
From Latin 'interesse' meaning 'to be between, to matter, to be of importance', from 'inter-' (between) + 'esse' (to be). The financial sense grew from the idea of something that ‘concerns’ or ‘matters’ to someone’s money.
The same word covers curiosity and money growth, which is revealing: both are about your resources (attention or cash) increasing over time. Compound interest in money is powerful—but compound interest in learning is even more explosive.
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