An incomplete glossary of selected terms from the BJD subculture, assuming that the reader at least knows what a BJD is:
Adoption: the process of buying a BJD on the secondary market. Some people use an extended metaphor of their BJDs as children.
Blushing/Brushing: application of chalk pastels and/or acrylic paint to a BJD’s body to represent variations in skin tone. Called "blushing" when applied to a doll’s head, but "body blushing" when applied elsewhere.
Bonding: emotional attachment that an owner ostensibly develops to a BJD.
Boy/Girl: a BJD, depending on the assigned sex of the doll, almost always used with possessive pronouns [e.g., "My girl looks so cute holding your boy!"] as part of the BJD:child metaphor.
Dolly diet: restriction of BJD-related purchases, usually because one has recently overspent.
Event head: a limited edition head issued by a BJD company as part of a sales event.
Faceup: hand-painted blushing, eyebrows and lips on a BJD’s head. Term seems to be a combination of "face" + "makeup."
Fullset: a limited edition BJD sold with a particular faceup, eyes, wig, outfit and sometimes accessories. Also used as an adjective, as in, "I’m selling her with the fullset dress and bonnet, but keeping the shoes."
Group order: a business transaction headed by an organizer who combines many small orders into a single large one, takes orders for participants, then submits all the orders as a single large purchase to the doll company. Item prices factor in a base price, a percentage of shipping from the doll company to the organizer, then shipping and handling from organizer to partner. The organizer collects payment, places the order, receives the items, then ships them to participants.
Grail doll: the one particular BJD that someone really wants, but often has difficulty acquiring because of limited edition, scarcity, expense, etc.
Heel feet: BJD feet sculpted with toes flexed up so that a doll can wear high heels. Sometimes sculpted as a single piece with the calf to eschew ankle joints and add stability.
KIPS: small silicone discs used by Volks in a BJD’s joint sockets to help the doll pose better. A type of sueding.
Mod: either a truncation of "modify" or "modification." To make change to a BJD, usually through the addition of sculpting epoxy putty or through the use of sandpaper and other subtractive tools, or the change itself.
MSC: Mister Super Clear, a Japanese spray used to seal a faceup or body blushing.
MSD: Mini Super Dollfie, the line of ~40cm, 1:4 scale BJDs created by Volks. As the first commercially available BJDs of this size, they have also become the standard by which other dolls are measured. Thus MSD also refers more generically to the size of the doll, i.e., 40cm and 1:4 scale. Sellers of BJD clothes, accessories or props may refer to things as "MSD" or "MSD size," which does not necessarily imply any association with Volks MSDs.
NSFW/NWS: not safe for work/not work safe. These labels appear on shots of BJDs with visible nipples and/or genitalia that, it is assumed, may not be prudent to view at one’s workplace.
OC: original character or a BJD representation thereof, in implicit contrast to the many BJD representations of fictional characters from other media.
Recast: an illegally duplicated BJD, often much lower in price than the legitimate original. Recasts may be literal recasts, i.e., products of unauthorized use of official molds, or copies achieved by reverse-engineering a mold from an existing legitimate BJD.
Reshelling: deciding that a different type of BJD would make a better representation of a character [often an OC] than the doll one currently has, selling the current shell and buying a new one.
SD: Super Dollfie, the line of 60cm, 1:3 scale BJDs created by Volks. As the first commercially available BJDs of this size, they have also become the standard by which other dolls are measured. Thus SD also refers more generically to the size of the doll, i.e., 60cm and 1:3 scale. Sellers of BJD clothes, accessories or props may refer to things as "SD" or "SD size," which does not necessarily imply any association with Volks SDs.
Shell: a BJD representation of a fictional character, often an OC.
Sleeping head: a BJD head with fully or partly closed eyes. Fully closed eyes do not require the use of eyeballs and may not even have sockets, while partly closed eyes have sockets and can use eyeballs. There is no standard terminology for sleeping heads. One company’s "sleeping" [e.g., Fairyland] is another company’s "romantic" [Soom], "reminisce" [Elfdoll], "slack afternoon" [Dollshe], etc.
Split: a type of group order where an organizer advertises that they want to buy a doll, but only for certain parts. The remaining parts are then available for split partners to purchase. Group order procedures then follow. Also the act of selling parts of a doll separately on the secondary market.
Sueding: the addition of some type of grippy material to a BJD’s joint balls and/or sockets to help the doll hold poses better. Materials include suede, hot glue and KIPS discs.
Yellowing: the discoloration of a resin BJD when exposed to sunlight. May be counteracted to some degree by stabilizers that keep the resin pigmentation from changing too much, the addition of UV resistance to resin, coating the BJD with MSC or another sealant or just keeping the doll in the dark, but is ultimately inevitable.