तिथि
tithi
TI-thi (both t's are soft dental, 'i' as in 'it', stress on first syllable)
Level 2Etymology
Root: Derived from the Sanskrit root √tan (to extend, to stretch), suggesting the 'extension' or measured progression of lunar time. Some traditional grammarians also connect it to √ci (to observe, to reckon). The word is feminine in gender (tithiḥ, nominative singular).
Literal meaning: A measured unit of lunar time; a reckoning or counted portion of the Moon's journey relative to the Sun.
Definition
A tithi is one lunar day in the Hindu calendar (pañcāṅga), defined as the time it takes for the longitudinal angle between the Moon and the Sun to increase by exactly 12 degrees. There are 30 tithis in a complete lunar month — 15 in the bright half (śukla pakṣa) and 15 in the dark half (kṛṣṇa pakṣa). Tithis determine the dates of festivals, vratas, śrāddhas, and all religious observances.
Each tithi carries a distinct spiritual energy (śakti) presided over by a specific deity, making it a vehicle for aligning individual sādhana with cosmic rhythms. The waxing tithis symbolize the progressive illumination of consciousness, while the waning tithis represent the withdrawal of awareness inward toward its source. Observing tithis cultivates attunement to the subtle interplay of solar (consciousness) and lunar (mind) forces within the practitioner.
At the transcendent level, tithi represents the eternal dance of Prakṛti measured against the unchanging light of Puruṣa — the Moon of the mind reflecting the Sun of pure awareness in ever-shifting degrees. The full cycle of tithis from Pratipadā to Amāvāsyā and back mirrors the pulsation (spanda) of manifestation and dissolution within Brahman. The one who realizes that all tithis arise and dissolve in timeless awareness has transcended kāla itself.
Appears In
Common Misconception
Many assume tithis correspond one-to-one with solar calendar days. In reality, because a tithi is defined by a 12-degree lunar arc (not by sunrise-to-sunrise), a tithi can be shorter or longer than a solar day. This leads to 'kṣaya tithi' (a tithi that begins and ends within one sunrise period and is thus skipped) and 'vṛddhi tithi' (a tithi spanning two sunrises, causing it to be counted twice). The calendar date of a festival can therefore shift in ways that seem inconsistent unless this astronomical basis is understood.
Modern Application
Understanding tithis reconnects modern practitioners with natural biorhythms that industrial schedules have displaced. Ekādaśī fasting, observed on the 11th tithi of each fortnight, aligns with documented shifts in ocean tides and bodily fluid balance caused by lunar gravitational pull. Planning meditation intensives around Amāvāsyā (new moon) or Pūrṇimā (full moon) tithis leverages the subtle but measurable effects of lunar phases on mental activity. Even secular applications benefit — farmers using tithi-based planting calendars report consistency with modern agronomic research on lunar influence on soil moisture and germination. For anyone seeking to live more harmoniously with nature's cycles, the tithi system offers a time-tested, observation-based framework.
Related Terms
Quick Quiz
How is a tithi astronomically defined?