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Ingredient index
Short, neutral meanings for the words you see on skin care labels. Definitions, not endorsements.
A
- Active ingredient
- In product listings, an ingredient the maker highlights as the main reason for using it. On sunscreens, active ingredients appear in a separate “Drug Facts” panel.
- Aqua / water
- Often the first ingredient. It is the base that other ingredients are dissolved or blended into.
B
- Broad spectrum
- A sunscreen label term meaning the product is labeled to cover UVA as well as UVB rays.
E
- Emollient
- A softening ingredient, such as a plant oil or butter, that helps skin feel smoother.
- Exfoliant
- An ingredient or tool that helps remove dead surface skin cells. Directions on how often to use it matter.
F
- Fragrance / parfum
- A catch-all word for scent ingredients. The individual scent ingredients are often not listed separately.
G
- Glycerin
- A common humectant, widely used in moisturizers.
H
- Humectant
- An ingredient that attracts water. Glycerin and hyaluronic acid are examples.
- Hypoallergenic
- A maker’s term suggesting a product is less likely to cause a reaction. It is not a promise and has no single legal definition.
N
- Non-comedogenic
- A maker’s term meaning the product is formulated to avoid clogging pores. It is a label claim, not a guarantee.
O
- Occlusive
- An ingredient that forms a layer on the skin to slow water loss, such as petrolatum or certain waxes.
P
- Patch test
- A small trial of a product on a small area of skin before wider use.
- PAO symbol
- The open-jar symbol with a number and the letter M. It shows the months the product is meant to be used after opening.
- Preservative
- An ingredient that helps keep a product from spoiling. Products that contain water generally need one.
S
- SPF
- Sun protection factor. A number describing protection against UVB rays under test conditions.
V
- Vehicle
- The base the active ingredients travel in, such as a cream, gel, lotion or oil.
General information only. A definition is not a recommendation. Serumelo is a health and beauty information website, not a medical provider, clinic, pharmacy, or retailer. It makes no medical claims, sells no products, does not diagnose or treat, and does not share your details with any partner.
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