The body (rupa [ruupa])* is like a "glob of foam"

On one occasion the Blessed One was staying among the Ayojjhans on the banks of the Ganges River. There he addressed the monks: "Monks, suppose that a large glob of foam were floating down this Ganges River, and a man with good eyesight were to see it, observe it, & appropriately examine it. To him ... seeing it, observing it, & appropriately examining it ... it would appear empty, void, without substance: for what substance would there be in a glob of foam? In the same way, a monk sees, observes, & appropriately examines any form that is past, future, or present; internal or external; blatant or subtle; common or sublime; far or near. To him ... seeing it, observing it, & appropriately examining it ... it would appear empty, void, without
substance: for what substance would there be in form (Body orRupa*)?-Phena Sutta -Foam

rupa [ruupa]:Body; physical phenomenon; sense datum. The basic meaning of this word is "appearance" or "form." It is used, however, in a number of different contexts, taking on different shades of meaning in each. In lists of the objects of the senses, it is given as the object of the sense of sight. As one of the khandha, it refers to physical phenomena or sensations (visible appearance or form being the defining characteristics of what is physical). This is also the meaning it carries when opposed to nama, or mental phenomena.

*Rupa