Harshana is the fourteenth nityayoga, and its name means joy, delight, and rejoicing. It is one of the auspicious yogas, favourable for celebrations, festivities, and undertakings connected with happiness and pleasure. Reckoned like the others from the summed longitude of Sun and Moon divided into twenty-seven parts, it advances as the lights separate through the lunar month. In the panchanga it lends its joyful quality to the reckoning of an auspicious moment, one of the five daily limbs consulted for muhurta. These are the conventions of the calendar tradition, in which a benefic yoga such as Harshana commends a time for gladness; the underlying reality is the combined motion of Sun and Moon through the month.
Harshana, joy or delight, shares its root with Harsha, a common personal name in Sanskrit and later Indian languages still given today, and with harsholhas, exuberant rejoicing, a compound occasionally found in classical descriptions of festival crowds. The root hrish, to bristle or thrill with delight, that underlies all these forms originally describes a physical reaction, the hair standing on end from strong emotion, before it broadened to cover joy in general, so the yoga's name carries, at its etymological root, an image of visible, bodily excitement rather than a purely inward or abstract contentment.