periapsis noun2 •The point of a body's (elliptical) orbit in a 2-body gravitational system such that the distance between the two bodies (measured from their respective centres of mass) is at its minimum.The main aerobraking phase began once the point of the spacecraft's periapsis had been lowered to within 110 km above the Martian surface. — 2004 •The minimum distance between the two bodies in such a system. formsperiapses · periapsides · periapsises
