Type of signaling in which a cell secretes into the intercellular space a molecular messenger that diffuses and binds to receptors on nearby target cells, producing a signal in those cells.
Source:
PAC, 2016, 88, 713. 'Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)' on page 790 (https://doi.org/10.1515/pac-2015-1202)