Accord: the perfumery equivalent to a chord in music. It is a blend of two or more smells that produce a third and distinctive smell. An accord may be a simple mixture or consist of many components and applies when each component material is in balance and harmony with each other material so that no single component can be detected.
Aroma chemical: any chemical compound created and used for its aromatic properties. Aroma chemicals could be isolates of essential oils, the chemical modification of those isolates or synthetic compounds from petrochemicals.
Body: the main fragrance theme – the middle note or “heart” of a perfume. It is also used to describe a fragrance that is well-rounded or full.
Balanced: when a fragrance has been so carefully blended that no single aromatic body or effect is readily identifiable.
Bottom (base) note: the underlying components of a fragrance, responsible for its lasting qualities, often referred to as fixatives.
Bridge: the ability of a scent (single oil or accord) to connect two notes of a fragrance and thus smooth the transition from one phase to another.
Character: the distinct impression that the fragrance gives (fresh, fruity, floral…).
Diffusion: the degree in which the fragrance radiates from the product or the user after the application of the product.
Dry down: the final phase of a fragrance – the bottom note, the character which appears several hours after application. Perfumers evaluate the bottom (base) notes and the tenacity of the fragrance during this stage.
Fixative: a material used in a perfume to “fix” the perfume or make it last longer. Fixatives may be simply materials that are relatively longer lasting than the other components or they may have some physical or chemical effect of forming bonds with the other materials.
Lift: the impact of a fragrance. Highly diffusive fragrances have a good “lift”.
Middle (heart) note: the core of a perfume composition which gives it its character. The middle or “heart” note makes up the main part of a fragrance and determines the classification or fragrance family.
Note(s): one of three distinct periods in the evaporation of a perfume, (see: top note, middle note, bottom note). This also indicates an olfactory impression of a single smell.
Thread: the term “common” thread describes a fragrance’s ability to flow from one phase to another in a cohesive rather than a discordant fashion.
Top note: the impression of a fragrance when first smelled or applied to the skin, usually the most volatile ingredients in a perfume. The materials identify the formulation that show themselves and identify the first stages of evaporation.
Volatility: the degree in which a component freely diffuses into the atmosphere.
