What is the scientific name for a bump? Understanding Medical Terminology

October 1, 2025 •

4 min read

According to the Cleveland Clinic, a skin lesion is any area of the skin that is abnormal compared to the surrounding skin. Therefore, what is the scientific name for a bump? This seemingly simple question has a complex answer, as the generic term refers to numerous medical conditions that require more specific terminology depending on their characteristics.

Quick Summary

The scientific name for a bump depends on its specific characteristics. Medical professionals use precise terms like papule, nodule, or cyst to classify bumps based on their size, composition, and location.

Key Points

No Single Scientific Name: There is no one scientific name for a bump; instead, dermatologists use specific medical terms based on the bump's characteristics.
Papules and Nodules: A papule is a small, solid, raised bump, while a nodule is a larger, deeper, and firmer elevated lesion.
Cysts are Encapsulated: Cysts are sac-like pockets enclosed in tissue and often filled with fluid, pus, or other material, distinguishing them from solid bumps.
Fluid-Filled Lesions: Pustules contain pus, while vesicles (small) and bullae (large) are blisters filled with clear fluid.
Monitor for Changes: While most bumps are benign, the ABCDE rule can help identify suspicious characteristics that may indicate skin cancer, such as asymmetry or evolving size.
Seek Medical Advice for Concerns: Rapidly growing, painful, bleeding, or unusually shaped bumps should be evaluated by a healthcare professional for a proper diagnosis.

The scientific terminology for different types of bumps

The word 'bump' is a general term, but in dermatology, a more precise vocabulary is used to describe different types of raised skin lesions. These medical terms help doctors accurately diagnose and treat the underlying condition. Here is a breakdown of the most common scientific names for a bump:

Papule

A papule is a small, solid, raised bump on the skin that is typically less than 1 centimeter in diameter. It is a very common type of skin lesion and can be associated with various conditions. Examples of papules include:

Small pimples (a type of acne)
Warts
Some moles (nevi)
Insect bites

Nodule

When a solid, raised lesion is larger than a papule (greater than 1 centimeter), it is called a nodule. Nodules extend deeper into the dermis or subcutaneous tissue, giving them a firm, palpable feel. Conditions that present as nodules include:

Cysts
Lipomas
Fibromas

Cyst

A cyst is a closed pocket of tissue that is encased in a wall or capsule. Unlike solid bumps, cysts are typically filled with fluid, pus, air, or other material, like keratin. They can feel soft or firm and can form for a variety of reasons, including infection or a clogged oil gland. A true sebaceous cyst, though a commonly misused term, is less common than an epidermal inclusion cyst.

Pustule

A pustule is an elevated, fluid-filled bump containing pus. These are a hallmark of many inflammatory skin conditions, and their red or inflamed base distinguishes them from other lesions. The most common example is a whitehead associated with acne. Folliculitis, an infection of the hair follicle, can also appear as pustules.

Vesicle and Bulla

Vesicles are small, fluid-filled blisters that are less than 1 centimeter in diameter. Bullae are larger blisters, measuring greater than 1 centimeter. Both can result from friction (e.g., shoe rub), burns, or certain autoimmune conditions. For example, vesicles are characteristic of herpes infections.

Wheal

A wheal is a raised, irregularly shaped, and often itchy patch of skin caused by localized swelling. Also known as hives or welts, wheals often appear as an allergic reaction to medications, insect stings, or other stimuli. They are typically transient and can appear and disappear quickly.

Lipoma

A lipoma is a specific type of benign (noncancerous) tumor composed of fatty tissue. These soft, rubbery, and slow-growing lumps are located just beneath the skin and are often movable when touched. They are very common and usually painless unless they grow large enough to press on a nerve.

Comparing Different Types of Bumps


Feature	Papule	Nodule	Cyst	Pustule	Lipoma
Size	Less than 1 cm	Greater than 1 cm	Varies	Less than 1 cm	Varies
Composition	Solid	Solid	Fluid, pus, or keratin	Pus	Fatty tissue
Firmness	Firm	Firm	Firm or soft	Soft (fluid)	Soft and rubbery
Depth	Epidermis/dermis	Dermis/subcutis	Dermis/subcutis	Epidermis	Subcutis
Mobility	Fixed	Fixed or mobile	Fixed or mobile	Fixed	Mobile

Common causes of bumps on the skin

Skin bumps can arise from a wide range of causes, from benign conditions to more serious ones. Some of the most frequent causes include:

Infections: Bacterial infections can lead to boils, carbuncles, and impetigo. Viral infections can cause warts (HPV) and herpes (HSV). Fungal infections can also manifest as skin lesions.
Inflammation: Clogged hair follicles due to oil and dead skin cells result in acne, which can include papules, pustules, and nodules. Folliculitis is another example of inflamed hair follicles.
Benign Growths: Conditions like lipomas, skin tags (acrochordons), and cherry angiomas are common, harmless, noncancerous growths.
Trauma: An injury can cause localized swelling or a bruise, often colloquially called a "goose egg".
Allergic Reactions: Hives (wheals) are a classic example of skin bumps resulting from an allergic reaction to food, medication, or environmental irritants.

When should you see a doctor?

While most bumps are harmless, some can indicate a more serious condition, such as skin cancer. It is important to monitor any skin lesion and seek medical advice if you notice any of the following warning signs, often summarized by the ABCDE rule for melanoma detection:

Asymmetry: One half of the bump doesn't match the other.
Border: The edges are irregular, ragged, or blurred.
Color: The color is uneven, with different shades of brown, black, or even red, white, or blue.
Diameter: The bump is larger than 6 millimeters (about the size of a pencil eraser).
Evolving: The bump changes in size, shape, or color over time.

Other reasons to see a doctor include a bump that is painful, bleeds, or shows signs of infection like increased redness or pus.

Conclusion

In medicine, there is no single scientific name for a bump. Instead, healthcare professionals use a variety of precise terms to describe different kinds of skin lesions, with the specific term depending on the characteristics of the bump itself. Terms like papule, nodule, cyst, and pustule all describe a type of skin bump, but each has a distinct meaning related to its size, composition, and location within the skin layers. While many bumps are benign, understanding the signs that warrant a medical evaluation is crucial for proper health management. If you are concerned about any new or changing skin lesion, consulting a healthcare provider or a dermatologist is always the best course of action.

Frequently Asked Questions

The medical term for a small, solid, raised bump on the skin, typically less than 1 centimeter in diameter, is a papule.

A firm bump under the skin is often referred to as a nodule. These lesions are generally larger than a papule and extend deeper into the skin layers.

A small bump containing pus is medically known as a pustule. A common example is a pimple associated with acne.

A soft, fatty bump that grows under the skin is called a lipoma. These are benign and usually painless unless they grow large enough to press on a nerve.

A blister is medically referred to as a vesicle if it is less than 1 centimeter in diameter or a bulla if it is larger.

The scientific name for a skin tag, a common, soft, fleshy growth, is acrochordon.

You should consult a doctor about a skin bump if it is asymmetrical, has an irregular border, changes color or size, or is larger than 6 millimeters. Pain, itching, or bleeding are also reasons for concern.