Janardana is another name of Vishnu

Vishnu

Vishnu is the Supreme god in the Vaishnavite tradition of Hinduism. Smarta followers of Adi Shankara, among others, venerate Vishnu as one of the five primary forms of God....

 or God and appears as the 126th name in the Vishnu sahasranama

Vishnu sahasranama

The Vishnu sahasranama is a list of 1,000 names of Vishnu, one of the main forms of God in Hinduism and the personal supreme God for Vaishnavas . It is also one of the most sacred and commonly chanted stotras in Hinduism...

. It is also a common name of Krishna

Krishna

Krishna is a central figure of Hinduism and is traditionally attributed the authorship of the Bhagavad Gita. He is the supreme Being and considered in some monotheistic traditions as an Avatar of Vishnu...

 being address as such by Arjuna

Arjuna

Arjuna in Indian mythology is the greatest warrior on earth and is one of the Pandavas, the heroes of the Hindu epic Mahābhārata. Arjuna, whose name means 'bright', 'shining', 'white' or 'silver' Arjuna (Devanagari: अर्जुन, Thai: อรชุน, Orachun, Tamil: Arjunan, Indonesian and Javanese: Harjuna,...

 in the Bhagavad Gita

Bhagavad Gita

The ' , also more simply known as Gita, is a 700-verse Hindu scripture that is part of the ancient Sanskrit epic, the Mahabharata, but is frequently treated as a freestanding text, and in particular, as an Upanishad in its own right, one of the several books that constitute general Vedic tradition...

.

According to Adi Sankara' s commentary on the Vishnu sahasranama

Vishnu sahasranama

The Vishnu sahasranama is a list of 1,000 names of Vishnu, one of the main forms of God in Hinduism and the personal supreme God for Vaishnavas . It is also one of the most sacred and commonly chanted stotras in Hinduism...

, translated by Swami Tapasyananda, Janardana means "One who inflicts suffering on evil men." Alternatively, it means, "He to whom all devotees pray for worldly success and liberation."