tissue

https://doi.org/10.1351/goldbook.09652
Group of biological cells that perform a specific function.
Note: A cellular organizational level intermediate between cells and complete organs.
Source:
PAC, 2018, 90, 1121. 'Terminology of bioanalytical methods (IUPAC Recommendations 2018)' on page 1126 (https://doi.org/10.1515/pac-2016-1120)