Wiktionary
y-intercept
n. (context maths English) A point at which a line crosses the y-axis of a Cartesian grid.
Wikipedia
Y-intercept
In analytic geometry, using the common convention that the horizontal axis represents a variable x and the vertical axis represents a variable y, a y-intercept is a point where the graph of a function or relation intersects with the y-axis of the coordinate system. As such, these points satisfy x = 0.