Pascal
Definition
The SI unit of pressure. One pascal is one newton of force spread over one square meter — a very small pressure, so real-world pressures are usually given in kilopascals.
Symbol: · Unit: pascal (Pa)
Technical definition
The SI derived unit of pressure and stress, named for Blaise Pascal: 1 Pa = 1 N/m² = 1 kg/(m·s²). Standard atmospheric pressure is 101,325 Pa.
Example
Normal atmospheric pressure is about 101 kPa. A car tire is inflated to roughly 200–250 kPa, while the pressure at the bottom of the Mariana Trench exceeds 100,000 kPa.
The pascal (unit) and Pascal's principle are named after the same person but are different things — one is a unit of pressure, the other is the law that pressure applied to a fluid spreads undiminished. Also note the capital P in the symbol Pa.