In common parlance all the Buddhas and bodhisattvas can be called Lokanath i.e Lord of the world but in a specific sense Lokanath is one of the forms of Avalokiteshvara. Nepalese texual
sources describes him thus:

Lokanath Lokeshvara is white in colour. Lokanath Lokeshvara sits in the Lalita attitude. In his matted hair the figure of Vajradharma exhibiting varadamudra in the right hand and holding lotus in his left hand appears. Lokanath Lokeshvara is said to have originated from the seed syllable Hrih. Lokanath Lokeshvara exhibits varadamudra with his right hand and holds a lotus in the left. In the Lokanath mandala, he is said to be surrounded by Tara to his right and Hayagriva on the left. A host of eight bodhisattvas and others surrounds him. The image of this form of Lokeshvara is very rare. Both the Padmapani and Lokanatha hold the Lotus with their left hands and this creates confusion in identification.