8 terms

Midsegment

Segment that joins that midpoints of two sides of a triangle

Perpendicular Bisector

Segment that is perpendicular to the side of a triangle at its midpoint

Circumcenter

Point of concurrency for the perpendicular bisectors of a triangle

Angle Bisector

Segment that bisects an angle of a triangle and its endpoints are a vertex and a point on the opposite side

Incenter

Point of concurrency for the angles bisectors of a triangle

Median

Segment whose endpoints are a vertex and the midpoint of the opposite side

Centroid

Point of concurrency for the medians of a triangle

Altitude

Segment with an endpoint on a vertex and perpendicular to the opposite side or the line containing the opposite side