Definition of energy

The word "energy" has its roots in ancient Greek philosophy. The term "ἐνέργεια" (energeia) was coined by Aristotle (384-322 BCE) to describe the actuality or realization of a potentiality. Later, the Stoic philosopher Galen (129-216 CE) used the term to describe the vital force or power that drives living beings. The modern English word "energy" emerged in the 17th century, derived from the Middle French "énergie", which in turn was borrowed from the Greek "ἐνέργεια". The concept of energy was further developed by scientists such as René Descartes and Sir Isaac Newton, who identified it as a measurable and quantifiable property. Today, the term "energy" refers to the ability or capacity to do work, often measured in units such as joules or kilowatt-hours. Despite its origins in ancient philosophy, the modern concept of energy has its roots in the scientific revolution of the 17th century.