闹革命 is a verb-object separable compound (离合词) meaning 'to carry out a revolution' or 'to make revolution'. The verb 闹 (nào) literally means 'to stir up / to cause', and 革命 (gémìng) is the noun 'revolution'. Because it's separable, you can insert 了, 过, duration phrases, or measure words between the two parts: e.g. 闹了三次革命 ('staged three revolutions'), 闹过革命 ('have made revolution'). The full form is used to refer to revolutionary political activity, especially in 20th-century Chinese history, and the separated form is common in speech.