Bicyclic alkenes having a double bond between the bridgehead atoms and a transattachment of each branch to the double bond. Thus trans-bicyclo[m.n.0]alk-1 (m+2)-enes.
Source: PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1322 [Terms] [Paper]