Solid

Example:

Imagine trying to fit a large, bulky sofa through a narrow doorway when moving into a new apartment. Just like the sofa maintains its distinct shape and size regardless of how you try to maneuver it, a solid maintains its definite shape and volume irrespective of the space it occupies. In this analogy, the sofa represents a solid, with its unchanging dimensions symbolizing the fixed shape and volume characteristic of solid matter, while the doorway represents the space around it that does not alter the sofa's inherent properties.