The Sivalik hills is a mountain range of the outer Himalayas also known as Manak Parbat in ancient times. Shivalik literally means 'tresses of Shiva’. This range is about 2,400 km (1,500 mi) long enclosing an area that starts almost from the Indus and ends close to the Brahmaputra, with a gap of about 90 kilometres (56 mi) between the Teesta and Raidak rivers in Assam. The width of the Shivalik hills varies from 10 to 50 km (6.2 to 31 mi), their average elevation is 1,500 to 2,000 m (4,900 to 6,600 ft).

Other spelling variations used include Shivalik and Siwalik, originating from the Hindi and Nepali word 'shiwālik parvat' शिवालिक पर्वत. Other names include Churia hills Nepali: चुरिया पर्वत, Chure hills Nepali: चूरे पर्वत, and Margalla hills.