Estimation
For an unknown parameter $\theta$ in the population distribution, we construct a statistic $\hat \theta(X_1, X_2, …,X_n)$ to give an estimation, we call $\hat \theta(X_1, X_2, …,X_n)$ an estimator, $\hat \theta(x_1, x_2, …,x_n)$ an estimated value.
Without making confusion, call estimator and estimated value collectively estimation.