The state in which a substance has no tendency to flow under moderate stress; resists forces (such as compression) that tend to deform it; and retains a definite size and shape WordNet 3.0 & Open English WordNet

| list1name = laws | list1title = Laws | list1 = | list2name = solid | list2title = Solid mechanics | list2 = | list3name = fluid | list3title = Fluid mechanics | list3 = | list4name = rheology | list4title = Rheology | list4 = | list5name = scientists | list5title = Scientists | list5 = }} Solid is one of the four fundamental states of matter along with liquid, gas, and plasma. Wikipedia

One of the four fundamental states of matter. Wikipedia Disambiguation

Solid matter; matter which does not deform easily under pressure Wikidata

A fundamental state of matter that retains its size and shape without need of a container. OmegaWiki

The physical state of matter in which the constituent molecules, atoms, or ions have no translatory motion although they vibrate about the fixed positions that they occupy in a crystal lattice. OmegaWiki

A substance in the fundamental state of matter that retains its size and shape without need of a container (as opposed to a liquid or gas). Wiktionary

Chemistry: fundamental state of matter. Wiktionary (translation)