Glossary

The range of poses a BJD can achieve. Heavily influenced by whether elbow and knee joints are single or double.

A purchase option that includes the doll body only. Faceup, eyes, and clothing are sold separately.

Ball-Jointed Doll. A doll whose parts are connected at ball-shaped joints and held together by internal elastic tension cord, allowing free posing.

The torso and limbs. Detachable from the head. Humanoid BJD bodies are generally designed to approximate real human proportions.

The process of pouring liquid resin into a silicone mold and curing it to reproduce parts.

A certificate issued by the maker with every authentic doll, used to verify authenticity during second-hand transactions.

Modifying the head or body with sandpaper, putty, and similar tools to reshape the sculpt — for example, turning an open-eyed head into a half-open or closed one.

A storefront that carries multiple BJD brands on behalf of their makers, letting buyers order from several brands in one place.

The maker's default specification. A 'default faceup' is the makeup applied at the factory. More recently, owners also use the term for the faceup and outfit they consider their doll's standard look.

A practice of keeping a doll permanently on display on a desk. A term used by owners who accept the accelerated yellowing in exchange for being able to see the doll every day.

A catch-all term for people who own dolls or participate in related communities and the culture around them.

A structure with two joint balls stacked vertically, allowing the limb to bend twice. Enables poses that are difficult with single joints, such as kneeling or sitting on heels. Structures sometimes labeled 'triple joint' are in practice double joints.

Doll eyeballs. Made from acrylic, glass, resin, silicone, and other materials. Size is given in millimeters.

The process of applying makeup to the face with pastels, acrylic paint, colored pencils, and similar media. Matte-coat sprays are applied before and during the work to seal the resin surface. Oil pastels and oil paint are avoided because the oil base penetrates the resin.

The state of the doll standing unassisted, held up by tension alone. A stand is recommended when wearing heeled feet or legs.

A greenish discoloration of urethane, another characteristic symptom of resin aging alongside yellowing.

The head of the doll. Some brands sell heads separately. Head sculpts are broadly categorized as realistic, semi-realistic, or anime (2D-style) molds.

A classification of how far the iris protrudes on a doll eye. High-dome eyes can sit too high in a half-open head sculpt, so dome height should be matched to the head.

Thin silicone pieces inserted between joints. They increase friction and stabilize poses; also used to adjust neck fit when hybridizing heads and bodies from different brands.

A release capped by quantity or time. These often command a premium on the second-hand market.

The original sculpt used as the starting point for production. May be hand-sculpted in clay or putty, or digitally modeled in 3D.

The form used to cast heads and bodies. Dolls cast from the same mold share the same sculpt. The master is cast in silicone to produce the mold, and resin is poured into the mold to reproduce parts.

A production model in which the doll is cast after the order is placed. Lead time is typically 2–3 months.

The standard skin tone of a doll. Usually in the ivory-to-peach range.

A classification of how the eye area is sculpted. The same base sculpt looks very different across open, half-open, and closed versions; makers sometimes release several eye variants of a single master.

A doll's owner. Widely used across the doll hobby community.

A service in which a maker replaces old, yellowed, or damaged parts for a fee below the original retail price. Requires proof of authenticity; rules and limits vary by maker.

The act of posing a doll. Achievable range depends on tension state and joint structure (single vs. double).

Reserving a product before its release. Because most BJDs are made to order, pre-ordering is the norm.

A counterfeit made by casting from an unauthorized mold of an original doll. Violates the original artist's intellectual property and is strongly rejected within the community.

Polyurethane resin. The standard BJD material. Excellent detail reproduction, but prone to yellowing and mildly toxic — upkeep requires some caution.

A silicone cap worn over the head. Improves wig grip and helps prevent dye transfer from dark-colored wig caps staining the resin.

A joint structure with one joint ball on a single side, bending only once. Range of motion is limited.

When dark-colored clothing or wig caps stay in contact with resin for too long, dye transfers to the surface. Can be wiped off early with a damp melamine sponge, but once it soaks into the resin it becomes permanent.

A brown-range skin tone, typically offered as a separate option.

The elastic cord that holds BJD parts together. It is a consumable — as it stretches out, the doll can no longer stand and joint balls rotate freely, requiring re-stringing.

A doll wig. Size is expressed as head circumference in inches. Most wigs are made of heat-resistant synthetic fiber or mohair.

Running craft wire through the tension channels to aid standing and posing. Can improve a body that poses poorly, but done badly it reduces articulation. Often commissioned to specialist shops.

Polyurethane resin turns yellow over time from exposure to air and UV light. The process begins the moment the resin contacts air. Dark storage and UV blocking only slow it; no method prevents it entirely.