_______ is the pressure that a fluid attains when it is brought to rest isentropically.

Explanation:

• Stagnation pressure, also called total pressure, is the pressure a fluid attains when brought to rest isentropically, meaning without any heat transfer or dissipation of mechanical energy (also assumes to be frictionless and adiabatic condition).
• In fluid dynamics, the mainstream flow velocity reduces as it approaches an obstruction, for example, the leading edge of an airfoil. According to Bernoulli's principles which govern fluid motion, the kinetic energy of the fluid is converted into pressure energy. As the velocity decreases to zero (reaches stagnation), all the kinetic energy is converted into pressure energy, resulting in a maximum (stagnated) pressure reading. This is called the stagnation pressure. It is often used in fluid dynamics and aerodynamics for calculations involving the energy of the flow.
   

To clarify some of the other terms:

Thermodynamic pressure: This is the fundamental concept of pressure in physics and engineering, not specific to fluid at rest or in motion. It is the force exerted by a substance per unit area.

Static pressure: It is the pressure of the fluid that is independent of the flow. In other words, it is the pressure measured when the fluid is at rest. Static pressure can also be considered as the pressure of the fluid on the walls of the container or pipe.

Dynamic pressure: This is the pressure exerted due to motion of the fluid. It is equivalent to half the fluid's density times the square of its speed. Dynamic pressure is one component of the total pressure exerted by a fluid, with static pressure and potentially also hydrostatic pressure comprising the other components.