Short answers, pulled from the story.
Lung, written in Tibetan as rlung, means wind or breath and is a key concept in Vajrayana traditions of Tibetan Buddhism. It refers to a subtle flow of energy most closely connected with the element of air, and encompasses psychic winds, vital breath, spiritual transmissions, and a system of five bodily winds used in traditional Tibetan medicine.
Traditional Tibetan medicine identifies five lungs: life-grasping lung located in the brain, upward moving lung in the thorax, all pervading lung in the heart, fire accompanying lung in the stomach and abdomen, and downward cleansing lung in the rectum and perineal region. Each regulates a distinct set of physiological and mental functions.
In Tibetan Buddhism, the subtle body, known as the Vajra body, is composed of winds, channels, and drops. Lung, especially the vital breath sog lung, moves through the invisible channels of the subtle body and is considered the essence of life itself. Practices such as tummo, one of the Six Yogas of Naropa, train practitioners to draw lung into the central channel.
Tsalung, spelled in Tibetan as rtsa rlung, are special yogic exercises used in the Bon tradition and the four main schools of Tibetan Buddhism. The Sanskrit equivalent is nadi-vayu. Tsalung exercises are employed in Trul khor yoga and in generation stage practices.
In Vajrayana Buddhism, lung names a type of tantric empowerment in which a master transfers spiritual power to a disciple through the recitation of scripture or song. This oracular transmission, received aurally, defines the Vajrayana and Ngagpa traditions and provides them with their nomenclature. A related form is the reading transmission of sutrayana texts, where a teacher reads an entire text aloud to a student.
Lung appears as a component in the term lung ta, which means Wind Horse and names a type of Tibetan prayer flag. The Wind Horse is an allegorical figure, and the lung component of the name connects the prayer flag tradition directly to the broader concept of wind energy in Tibetan religious culture.