Sillage

Sillage (from the French for a ship's wake) describes how much of the fragrance other people can smell at conversation distance and beyond. A fragrance with strong sillage projects across a room; one with intimate sillage stays close to the skin. Sillage is not the same as longevity — a fragrance can last 10 hours but stay skin-close the whole time. Both matter. Designer perfume bro culture overweights sillage to the point of being annoying; niche perfumery often deliberately tunes for skin-close intimacy. Neither is right or wrong — just different.