memory cell

https://doi.org/10.1351/goldbook.13452
Clonally expanded T cell or B cell produced during a primary immune response and which is primed to mediate a secondary immune response to the original antigen.
Source:
PAC, 2012, 84, 1113. (IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)) on page 1212 [Terms] [Paper]