Here's how the idiom is commonly interpreted:
* Right nostril: Someone is speaking well of you.
* Left nostril: Someone is speaking badly of you.
However, the actual origin of the idiom is unclear. Some theories suggest it's related to:
* Ancient belief: In some cultures, the nose was considered a connection to the soul or spirit, and itching was seen as a sign of supernatural activity.
* Physical sensations: Itching can sometimes be a sign of stress or anxiety, which might be related to a feeling of being watched or gossiped about.
It's important to remember that this is just an idiom and shouldn't be taken literally. It's a fun way to express a feeling of curiosity or suspicion.