9 terms

point of concurrency

The point of intersection of 3 or more lines

incenter

The point of intersection of the angle bisectors of a triangle

centroid

The point of intersection of the medians of a triangle

circumcenter

The point of intersection of the perpendicular bisectors of a triangle

orthocenter

The point of intersection of the altitudes of a triangle

altitude of a triangle

A line segment that connects the vertex of a triangle to the opposite side of the triangle and is perpendicular to that side

median of a triangle

A line segment that connects a vertex of a triangle to the midpoint of the opposite side of the triangle

angle bisector

A line segment that bisects an angle of a triangle

perpendicular bisector

A line segment that passes through the midpoint of a side of a triangle and is perpendicular to that side.