extracellular region https://github.com/geneontology/go-ontology/issues/31545 Note that this term is intended to annotate gene products that are not attached to the cell surface. For gene products at the cell surface, consider annotating to external side of plasma membrane ; GO:0009897. extracellular Wikipedia:Extracellular GO:0005576 The space external to the outermost structure of a cell. For cells without external protective or external encapsulating structures this refers to space outside of the plasma membrane. This term covers the host cell environment outside an intracellular parasite. cellular anatomical structure