Performance basics
Sillage meaning in perfume
Sillage describes the scent trail a fragrance leaves as the wearer moves. It is related to projection and persistence but does not mean the same thing as either a fixed distance around the wearer or total wear duration.
A HUME Fragrance buying guide

Think about movement
A trail noticed after someone passes differs from smelling perfume close to a stationary person. That distinction helps interpret reviews using the word sillage.
Avoid a universal trail standard
Different environments and application methods affect what another person notices. A statement about a trail is more useful when the setting is described.
Choose considerate presence
A prominent trail is not automatically desirable in shared spaces. Follow local fragrance rules and consider the actual occasion rather than seeking maximum noticeability.
Try this before you buy
Write whether a review describes a moving trail, surrounding presence or later close-range scent before using it to compare products.