Petrichor refers to the pleasant, earthy scent that rises when rain falls on dry soil or ground. The word comes from the Greek roots:
petra (πέτρα) meaning "stone"
ichor (ἰχώρ) meaning the fluid that flows in the veins of the gods in Greek mythology
So, it literally means “the blood of the stone.”
The smell comes from a combination of compounds:
Geosmin: produced by soil-dwelling bacteria
Plant oils: secreted during dry periods
Ozone: sometimes adds a fresh note
It’s strongly linked to memory and emotion for many people because of its sensory impact after drought or hot weather.
There’s something calming about the petrichor that lingers after a long-awaited rain.
