Final answer:
Ellipsoid (condylar) joints are classified as biaxial joints because they allow for movement along two axes.
Step-by-step explanation:
Based on the number of axes rotations, ellipsoid (condylar) joints are usually biaxial joints. These joints, such as the metacarpophalangeal joints (knuckle joints) of the hand, allow for movement in two planes: they enable flexion and extension, as well as abduction and adduction of the fingers. Condyloid joints consist of an oval-shaped projection of one bone fitting into the oval-shaped depression of another, allowing angular movements in two different directions.