A Plain-Language Glossary of Common Beauty Terms

Emollient

An ingredient that softens and smooths the skin by filling in gaps between skin cells. Emollients give products a creamy, luxurious feel and help maintain a healthy skin texture. Common examples include plant oils, shea butter, and fatty alcohols.

Humectant

A substance that draws moisture from the environment — or from deeper skin layers — into the outer layer of skin. Humectants like glycerin, hyaluronic acid, and aloe vera help keep skin feeling hydrated and plump.

Occlusives

Ingredients that form a physical barrier on the skin's surface to prevent water from evaporating. Petrolatum, beeswax, and dimethicone are common occlusives. They're especially useful for dry or compromised skin.

Hypoallergenic

A label claim indicating that a product is formulated to reduce the likelihood of an allergic reaction. It's important to note this is a marketing term with no standardized regulatory definition in the U.S., so reactions can still occur depending on individual sensitivities.

Non-comedogenic

Describes products formulated to avoid clogging pores. This term is commonly seen on moisturizers and foundations aimed at people with acne-prone or oily skin. Like "hypoallergenic," it's not a regulated claim, and individual skin responses can vary.

pH Balance

pH measures how acidic or alkaline a substance is on a scale of 0–14. Healthy skin typically has a slightly acidic pH (around 4.5–5.5). Products with a mismatched pH can disrupt the skin's natural barrier, leading to dryness or irritation.

Exfoliant

An ingredient or product that helps remove dead skin cells from the surface. Chemical exfoliants (like AHAs and BHAs) dissolve the bonds holding dead cells together; physical exfoliants (like scrubs) remove them through gentle abrasion.

AHA / BHA

Alpha hydroxy acids (AHAs) are water-soluble exfoliants — glycolic and lactic acid are common examples — that work on the skin's surface. Beta hydroxy acids (BHAs), primarily salicylic acid, are oil-soluble and can penetrate into pores, making them popular for acne-prone skin.

Antioxidant

A compound that helps neutralize free radicals — unstable molecules caused by sun exposure, pollution, and other environmental stressors that can damage skin cells. Vitamin C, vitamin E, and niacinamide are well-known antioxidants used in skincare.

Fragrance-Free vs. Unscented

Fragrance-free means no fragrance ingredients were added. Unscented means masking agents may have been used to eliminate a product's natural smell, which can still trigger sensitivities. Fragrance-free is generally the safer choice for sensitive skin.

Active Ingredient

In regulated products like sunscreens or acne treatments, active ingredients are those recognized as having a specific, proven therapeutic effect. They are listed separately on the label and must meet concentration requirements set by the FDA.

INCI Name

The International Nomenclature of Cosmetic Ingredients (INCI) system standardizes ingredient names on labels worldwide. That's why you'll see "aqua" instead of "water" or scientific Latin names for plant extracts — it ensures consistency regardless of where a product is sold.