The phrase "major rebellion" refers to a large and significant act of defiance or uprising against a governing authority or system. It often involves a large number of people who unite to challenge or overthrow those in power. Full definition
There were four major rebellions between 1236 and 1293 (A.D. 1820 - 76) (religion-online.org)
The Terrorism and Identity Cards bills saw major rebellions, but these both apply north of the border, so Scottish MPs can vote on them without quibbles. (channel4.com)
While everyone was concentrating on Miliband and Cameron, many people missed that Clegg suffered a major rebellion from his party on Syria. (politics.co.uk)