Literal translation
to be left holding a piece of nose
Meaning
to be left looking foolish
Explanation
The expression describes the disappointment of someone who, having hoped for or attempted something, ends up empty-handed and sheepish, pictured as carrying nothing but a piece of their own nose. The word pan here means a piece, a bit, a swath of cloth, the same sense found in French pan de mur or pan de chemise; paired with nas (nose), it forms an absurd, comic image close to the French pied de nez, a gesture of mockery or spite. The preposition em' is a contracted form of emé (with), very common in everyday speech and in rhythmic proverbs. The phrase describes a stinging failure, a dashed expectation, or a scheme that backfires on its author, in a familiar and rather mocking register, where the situation is laughed at as much as the person who suffers it.