Extraction by flow of sample through or over the extraction phase, or vice versa, to enhance the extraction rate.
Note: The forced flow of matrix or extraction phase is controlled by an external device.
Source:
PAC, 2016, 88, 517. 'Glossary of terms used in extraction (IUPAC Recommendations 2016)' on page 554 (https://doi.org/10.1515/pac-2015-0903)