A reciprocal relation of contained in, where given an immaterial continuant at some time, there is a material continuant contained in the immaterial continuant at the same time.

Intracellular Space of Tumor Cell contains Intracellular Fluid in a Tumor Cell

Smith B, Ceusters W, Klagges B, Kohler J, Kumar A, Lomax J, Mungall C, Neuhaus F, Rector AL, Rosse C: Relations in biomedical ontologies. Genome Biol 2005, 6: R46.