Oud, also known as agarwood, is a resinous heartwood that forms in the Aquilaria tree when it becomes infected with a specific type of mold. It's highly prized in perfumery for its rich, complex, and woody aroma with sweet, balsamic, and sometimes animalic undertones.

Oud brings a sense of luxury, depth, and sophistication to perfumes. Its scent is often described as intense, earthy, and sensual, adding depth and longevity to fragrances. Oud is frequently used as a base note in perfumery, anchoring and enhancing other fragrance ingredients. It's also known for its ability to evolve on the skin, creating a unique olfactory experience over time.