Perfumery talks to itself in a private vocabulary and then sells to people who were never given it. None of these words is difficult. They are simply rarely defined.
How a fragrance behaves
From the French for the wake a boat leaves. How far the fragrance travels from you, and what is left in a room after you have gone. A fragrance can last a long time and have almost no sillage — that is a close wearing, not a weak one.
How long it remains detectable on skin. Determined mostly by the weight of the base materials and by the skin it is on, not by price.
How forcefully it pushes outward, particularly in the first hour. Often confused with sillage; projection is the volume, sillage is the trail.
What remains after the volatile materials have gone — usually from three or four hours onward. For most wearers this is the majority of the experience and the part least often tested before buying.
How it is built
Several materials blended so they read as one smell that none of them is on its own. A "leather accord" contains no leather. This is the basic unit of composition.
A single perceived smell within the whole. Note lists describe what you are meant to perceive, not what is in the bottle — a listed note may be an accord, or a synthetic, or an impression.
Top, heart and base: the convention that a fragrance unfolds in three stages as lighter molecules evaporate first. A useful simplification rather than a description of how modern compositions are actually built.
A material that slows the evaporation of everything around it. Musks, resins and woods do this. It is why a base is not merely the last thing you smell but the thing holding the rest in place.
A note list is a description of an intention. It is not an ingredient list, and it was never meant to be read as one.
Materials
Obtained by distillation or by pressing. Available only from materials that survive heat — which excludes most delicate flowers.
Obtained with solvents rather than heat, giving a fuller, truer result from flowers that distillation would destroy. Jasmine and tuberose are normally absolutes.
The waxy intermediate stage between the flower and the absolute.
A material steeped in alcohol over weeks or months to draw out its smell. Slow, and used where nothing faster works.
An Indian distillate received directly into sandalwood oil rather than separated out. Worn neat, without alcohol.
A class of compounds giving a clean, abstract, slightly soapy lift. Chanel No. 5 made them famous in 1921 and they have never entirely left.
Families
Built on a contrast of bright citrus against oakmoss and labdanum. Named for Cyprus. Restrictions on oakmoss have changed how it is made, not whether.
Lavender, coumarin and oakmoss. French for fern, though it smells nothing like one. The backbone of most traditional men's fragrance.
Edible notes — vanilla, caramel, almond — used as perfume materials rather than as food references.
Resting the finished blend before bottling so the materials settle into each other. Weeks to months. Rarely mentioned, and audible in the result.