It looks like you may mean one of these two Jain terms (the spelling “ubdan” is often a typo):

1) Updaan (उपदान)

• Meaning: An earmarked religious donation offered with right intention (bhāva) for specific Jain purposes—like temple maintenance, pratimā/pratiṣṭhā events, gyan-yajna, āyambil/poshad-bhojan, pānjarāpol, pāṭhśālā, chaturmās arrangements, etc.
• Spirit: It should be given without pride or attachment, to a worthy purpose (patra) by rightful means (dravya), at the right time (kāla), with purity of intention. Both Digambar and Shwetambar communities use this term in community practice.

2) Updhān/Upādhān Tap (उपधान तप)

• Meaning: A rigorous layperson’s austerity performed mainly in the Śvetāmbara Mūrtipūjak tradition under guidance of sādhus/sādhvīs. It imitates a monk’s disciplined routine with cycles of fasting (upavās), ekāsan, pratikraman, kayotsarga, and regular recitation, typically observed in set spans (e.g., 47, 35, or 28 days) with defined sub‑phases.
• Aim: Deepen self‑discipline, reduce passions (kaṣāyas), and accumulate śubha‑puṇya while nurturing detachment (aparigraha).
• Note on traditions: The named vrata “Updhān Tap” is chiefly Śvetāmbara usage; Digambar Jains observe other extended tapas (like varṣītap), though the core spirit of tapa is common to both.

If you intended “Updaan” (donation), the essence is right giving with non‑attachment. If you intended “Updhān Tap” (austerity), the essence is disciplined observance modeled on sādhus, always under proper guidance.