A normalizable wave function is a mathematical representation of a quantum state that satisfies the condition of being square-integrable over its entire domain. This means that when you integrate the absolute square of the wave function over all space, the result is a finite value, allowing the total probability of finding a particle within that space to equal one. This property is essential for ensuring that the physical interpretations derived from the wave function are meaningful, particularly in the context of the Schrödinger equation and its solutions.