Species carrying two positive charges, formally located on tervalent carbon atoms, e.g.
+CH2–+CH2 ethane-1,2-diyl dication,
+CH2CH2–+CH2 propane-1,3-bis(ylium).
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1332 (https://doi.org/10.1351/pac199567081307)