unsolid

un- +‎ solid

unsolid (comparative more unsolid, superlative most unsolid)

1. Not solid.
   • 1690, John Locke, An Essay Concerning Humane Understanding, Volume I.‎:

     By this idea of solidity is the extension of body distinguished from the extension of space:--the extension of body being nothing but the cohesion or continuity of solid, separable, movable parts; and the extension of space, the continuity of unsolid, inseparable, and immovable parts.

   • 1921, Theodore Graebner, Evolution‎:

     And equally unsolid is the argument that from a principle of gradation in races would reduce a principle of progress in races.

• Loudins