Answer
$\color{blue}{\text{y-intercept}}$
Work Step by Step
RECALL:
(1) An x-intercept is a point were a graph touches or crosses the x-axis. Its coordinates are $(a, 0)$.
(2) A y-intercept is a point were a graph touches or crosses the y-axis. Its coordinates are $(0, b)$.
This means that the point $(0, 7)$ could be a y-intercept but not an x-intercept of a graph.
Thus, the missing expression in the given statement is:
$\color{blue}{\text{y-intercept}}$