Selective serotonin reuptake inhibitor. Selective serotonin reuptake inhibitors (SSRIs), also known as serotonin-specific reuptake inhibitors or serotonergic antidepressants,[1] are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder and anxiety disorders.
Then you're looking for the midpoint! The midpoint of a line segment is the point located midway between the endpoints of the line segment. This tutorial tells you about the midpoint of a line segment.
Noun. 1. midpoint-a point equidistant from the ends of a line or the extremities of a figure. centre, center. bight-the middle part of a slack rope (as distinguished from its ends). center of curvature, centre of curvature-the center of the circle of curvature. bowels-the center of the Earth.