A sequence of DNA lying beyond the 3' end of the coding segment of a gene which is recognized by RNA polymerase as a signal to stop synthesizing mRNA.
Source:
PAC, 1992, 64, 143. 'Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)' on page 166 (https://doi.org/10.1351/pac199264010143)