Bhūtas are grotesque goblins who form part of the army of Rudra-Śiva. Nīlalohita Rudra (one of the aspects of Śiva) is said to have created eleven crores of bhūtas. They are generally pictured as lean figures with elongated ears eager to trouble others. They often fought the asuras or demons siding with the gods.
Being the lord of these bhūtas, Śiva is often called ‘Bhūtanātha,’ ‘Bhūteśa’ or ‘Bhūteśvara’. Gaṇapati and Nandikeśvara also are sometimes called by this name.