Here's why and some possible options:
* Modern Invention: The concept of a bus is relatively modern, and Sanskrit, being an ancient language, doesn't have a word specifically for it.
* Possible Translations:
* "Sarvatra-gamana-yantra" (सरवत्र-गमन-यंत्र) - This literally translates to "all-going machine/vehicle," which could describe a bus's function of transporting many people to various places.
* "Bahujana-vahana" (बहुजन-वहन) - This means "vehicle for many people," which captures the essence of a bus.
* "Ratha" (रथ) - While traditionally referring to a chariot, it can be used in a broader sense to mean any vehicle. However, it might be less accurate for a modern bus.
* "Yana" (यान) - This is a general word for "vehicle" or "means of transport" and could be used as a generic term.
Ultimately, the best translation would depend on the specific context and the emphasis you want to convey.