Word

Harihara

Sanskrit

हरिहर

IAST

harihara

In General

Harihara is a combination two gods, Siva and Vishnu to form a single deity called Harihara. Hara(Siva) is always portrayed on the right side and Hari (Vishnu) on the left side.

The idea of Harihara is to tell devotees that all gods are same. It has got social, religious and philosophical aspect.

Sankara-Narayana is same concept.

Veda

Many of the Vishnu and Rudra hymns from RV call Siva as Vishnu and Vishnu as Siva.

Purana

Once the demon Guhasura obtained a boon from Brahma that neither Siva nor Vishnu should be able to kill him. When the atrocities of the demon become unbearable, the two devas joined together to become Harihara and killed him.