The probability of rejecting a null hypothesis when an alternative is true is called

The probability of rejecting a null hypothesis when an alternative is true is called the power of a test.

Power equals one minus beta, where beta is the probability of a type II error.

Probability level names the significance level alpha, not this rejection probability.

Contra acceptance is not a recognised statistical term.

Reality check is a colloquial phrase with no place in hypothesis testing.

Power rises with a larger sample, a bigger true effect and a higher significance level.