MT Esthetician key terms

An infection-control approach treating all blood, body fluids, and moist body substances as potentially infectious, so gloves and other barriers are used with every client regardless of known health status.

Using EPA-registered chemical products to destroy most pathogenic organisms on nonporous implements and surfaces, except bacterial spores. Required for tools that contact intact skin or are contaminated by blood or body fluids.

A process that destroys all microbial life, including bacterial spores, usually through autoclave steam under pressure, dry heat, or chemical sterilants. Required for implements that penetrate skin or contact blood.

Microorganisms such as hepatitis B, hepatitis C, and HIV that are transmitted through contact with infected blood or other potentially infectious materials. Exposure requires immediate washing and reporting under workplace exposure-control rules.

The presence of infectious material on a surface, tool, or skin. In esthetics, contamination occurs when an unclean implement, hands, or product touches a client or a clean supply.

The routine cleaning step that removes visible debris, oils, and residue from tools with soap and water before disinfection or sterilization, because disinfectants do not work reliably on soiled surfaces.

A manufacturer document, now commonly called a Safety Data Sheet, listing a product's hazardous ingredients, safe handling, first-aid measures, and storage requirements. Estheticians must know where these sheets are kept for salon chemicals.

The outermost, avascular layer of skin composed of stratified squamous epithelium. It renews itself through cell division in the basal layer and provides the primary barrier against water loss and microorganisms.

The outermost epidermal layer of flattened, keratin-filled dead cells embedded in lipids. It controls water loss and absorption, and its thickness and integrity shape how much product or exfoliation the skin tolerates.

The dominant epidermal cell type, produced in the basal layer and maturing upward into a hardened, water-resistant keratin cell before shedding. Its turnover cycle determines how quickly skin renews after exfoliation or injury.

A cell in the epidermal basal layer that produces melanin pigment and transfers it to nearby keratinocytes. Melanin absorbs ultraviolet radiation and determines skin and hair color; uneven activity causes pigmentation disorders.

An oil-producing gland attached to a hair follicle that secretes sebum onto the skin surface. Sebum lubricates skin and hair, and its overproduction contributes to oily skin, comedones, and acne.

A network of vessels and nodes that returns tissue fluid to the bloodstream and supports immune defense. Facial massage strokes generally follow lymph drainage pathways toward the nodes to reduce puffiness.

A classification of the skin's baseline oil and water balance, usually described as normal, dry, oily, or combination. Skin type is determined during consultation and guides product selection and treatment intensity.

A temporary or persistent abnormality visible on the skin, such as dehydration, acne, rosacea, or hyperpigmentation. Unlike skin type, conditions can change and may require modification or referral before treatment.

A six-category classification of skin based on how it responds to ultraviolet light, ranging from very fair to deeply pigmented. Estheticians use it to estimate burning and pigmentation risk during exfoliation and light-based services.

Darkened skin that develops after inflammation or injury, such as acne, waxing, or aggressive exfoliation, especially in darker skin tones. Prevention includes gentle technique, sun protection, and avoiding unnecessary irritation.

A hair follicle plugged with sebum and dead cells. An open comedone is a blackhead; a closed comedone is a whitehead beneath the skin surface. Comedones are a hallmark of acne-prone skin.

A condition or circumstance that makes a treatment inadvisable or requires modification, such as active infection, recent surgery, or pregnancy for certain ingredients. Identifying contraindications during consultation protects the client and the licensee.

A reason to avoid or limit facial massage, including active acne, open lesions, recent chemical peel, uncontrolled hypertension, or acute inflammation. Massage can spread infection and worsen inflammation in these situations.

A light, gliding massage stroke performed with the palms or fingers in the direction of lymph flow. It begins and ends most facial routines and promotes relaxation and circulation.

A kneading or compression massage movement that lifts and squeezes tissue to stimulate circulation and relax muscles. On the face it is applied with light finger pressure rather than deep hand pressure.

The active growth stage of the hair cycle, when hair is produced and the follicle extends deep into the dermis. Hair is most firmly anchored during anagen, though waxing still removes it.

The resting stage of the hair cycle, when growth stops and the hair is eventually shed. Follicles in telogen hold hair loosely, which can affect waxing results and regrowth timing.

The repeating sequence of growth, transition, and rest that every follicle follows, with phases lasting weeks to years depending on body area. Because follicles cycle independently, multiple waxing sessions are needed for smooth results.

Applying a small amount of product to a limited skin area before a full treatment to check for allergic or irritant reaction. It is especially important for wax, tint, adhesive, and chemical peel products.

Removal of dead surface cells using acids or enzymes such as glycolic, salicylic, or lactic acid. Strength, pH, and contact time determine depth, and client screening reduces risk of burns and pigmentation.

A water-soluble acid such as glycolic or lactic acid that loosens the bonds holding dead cells together, improving texture and tone. Concentration and pH determine its strength and irritation potential.

Stopping an acid peel's action by applying a neutralizing solution or otherwise raising pH at the correct time. Proper neutralization prevents excessive exfoliation, burns, and post-inflammatory pigmentation.

Acne-like breakouts triggered or worsened by comedogenic ingredients in cosmetics and skin-care products. Choosing noncomedogenic formulations and thorough cleansing helps prevent it.

A service that curls natural eyelashes using a chemical solution and silicone shield, lasting several weeks. Correct shield sizing and careful product placement prevent overprocessing and eye irritation.

A cyanoacrylate-based glue that bonds synthetic lashes to natural lashes. It cures with moisture and can irritate eyes or skin, so ventilation, isolation of lashes, and patch testing matter.

The principles of how colors combine and neutralize one another, used in makeup to correct discoloration. For example, green tones down redness and peach or orange tones down blue-toned darkness.

The legally permitted services and activities a licensed esthetician may perform under state law. Working outside it, such as diagnosing disease or using medical devices without authorization, risks license discipline.

A client's voluntary agreement to a service after being told its purpose, risks, alternatives, and aftercare. Documented consent supports client safety and provides evidence of professional communication.

A confidential intake and treatment history documenting allergies, medications, services performed, products used, and reactions. Accurate records support continuity of care and are often required by state rules.