बदबू आ रही है

You use this phrase just like you would say 'It smells bad' in English. It is a complete thought on its own. You can point at a trash can and say it. You can walk into a room and whisper it to a friend. It is very versatile because it works for almost any bad scent. Just remember that badbu is feminine, so we use rahi hai.

Use it when you find a forgotten sandwich in your bag. Use it if the fridge needs a deep clean. It is perfect for casual settings with family or friends. If you are at a street market and pass a sewer, this is what you say. It is also common when checking if milk has gone sour.

Avoid saying this directly to a person about their body odor. That would be considered very rude in Indian culture. Instead of saying it to their face, you might use a more polite hint. Do not use it for pleasant smells like flowers or perfume. For good smells, you must use the word khushbu instead. Using badbu for a nice candle would be very confusing!

In India, sensory experiences are often described as 'coming' or 'going'. We don't just 'smell' things; the smell 'comes' to us. This reflects a passive way of experiencing the environment. Hindi speakers are generally quite expressive about their surroundings. However, there is a strong social code about hygiene. Pointing out a bad smell in a public place is common, but pointing it out in someone's home requires more tact.

If the smell is really intense, add bahut to say bahut badbu aa rahi hai. If you want to ask 'Is it smelling bad?', just change your tone: badbu aa rahi hai?. You might also hear sadaand, which refers to a rotting smell. For a very faint bad smell, some might say ajeeb si mahak, which means a 'strange sort of scent'.