Someone types "dropping into pup space, handler has the leash" and you nod along without knowing whether that means a headspace, a gear list, or a scene about to start. It means all three, sort of, and this pet play glossary exists so you can read a room without asking. The vocabulary splits three ways, pup, kitten and pony, with a shared core underneath, and half the confusion comes from terms that mean something entirely different one room over.
Two rules before the vocabulary
These are stated first because they are not negotiable and they answer the two questions newcomers always arrive with.
Pets are humans in roles. Every person in pet play chat is a human playing at being an animal. Actual animals have no part in it, and bringing them into a scene is an instant ban.
Pet play is not furry. There is no fursona, no character with a name and a backstory and an art commission. A pup is you, in a headspace, being a dog. A fursona is a character you inhabit. The communities overlap socially, plenty of people do both, and you will see the same faces in furry chat, but the two are structurally different things and conflating them annoys everyone.
Shared terms across all pet play
Pet. The person in the animal role. Umbrella term covering pups, kittens, ponies, bunnies, foxes and anything else people take on.
Handler. The person on the other end of the dynamic. Most common word in pup circles, widely used everywhere else. A handler directs, rewards, corrects, and is responsible for the pet during and after a scene.
Owner. Heavier than handler, implying an ongoing dynamic rather than a scene. Carries the sense of belonging to someone.
Trainer. Focused on teaching behaviors, commands and routines. A trainer might not be the pet's owner at all, particularly in pony circles where training is a discipline of its own.
Pet space. The mental state where language and adult self-management drop away and simpler responses take over. The point of most of this. Related to but distinct from subspace.
Headspace. The general term for an altered mental state in a scene. Pet space is one flavor of it. People talk about dropping into it, and about the drop afterward, which is why aftercare matters.
Collar. Both a physical item and a statement. A play collar is gear for a scene. A relationship collar means something ongoing, and the distinction is taken seriously by people who use it, as collaring gets into properly.
Gear. Everything worn: hoods, mitts, tails, ears, harnesses, tack. Gear helps some people drop and is entirely optional for others. Text play needs none of it, which is a large part of why pet play works well in chat.
Mosh. Pets playing with pets rather than with a handler. Wrestling, tumbling, chasing, no hierarchy required. Originally a pup term, borrowed everywhere.
Primal. Instinct led play, growling and chasing and biting, without the pet role structure. Adjacent rather than identical: a pup is a dog, a primal is a predator or prey with no species costume. See primal play for where the line sits.
Puppy play terms
Pup. The person in the dog role. Also used as a title and a form of address.
Pup hood. The moulded or leather hood that makes a pup look like a dog. The iconic piece of gear and the one most people picture first.
Pup mitts. Padded gloves that close the hand into a paw. They remove fine motor control, which is the point, since you cannot use a phone with paws.
Mosh pit. A physical space at an event where pups play together. Online, the same word describes a room where several pups are interacting at once.
Woofing. Barking, huffing, and the general vocal register of pup play. In text it shows up as onomatopoeia and asterisked actions.
Alpha, Beta, Omega. Pack rank. An alpha leads, an omega sits at the bottom and often likes it there, a beta is somewhere in between. This is not the omegaverse sense. There are no heats, no ruts, no biology, no mating bonds. Someone using those words in the fiction sense has wandered in from monster roleplay and will confuse everybody. Pack rank is social hierarchy, nothing more.
Sir. Common form of address for a handler in pup circles, inherited from leather culture. Not automatic and not owed to a stranger.
Most of this vocabulary is in daily use in puppy play chat, where you will see it used rather than defined.
Kitten play terms
Kitten. The person in the cat role. Kitten play skews softer and more independent than pup play, and the dynamic tends to be less obedient by design.
Ears. The most common piece of kitten gear, usually a headband. Low cost, high effect, which is why it is where most people start.
Tail. Worn or clipped. In text it is a constant scene prop, since a tail flicks, curls and gives away mood.
Bell collar. A collar with a bell on it, so the owner always knows where the kitten is. Cute and quietly controlling at the same time, which is the whole appeal.
Bratty kitten. A kitten who disobeys on purpose to get a reaction. Not a failure state, an entire play style. Overlaps heavily with brat dynamics.
Lap cat. The opposite mode. Affectionate, sleepy, wants to be held and nothing else. Plenty of kitten scenes are entirely this, no sex involved.
Feral. A kitten who does not want to be tamed yet. Hissing, scratching, hiding under furniture, and being coaxed out slowly. Sits close to primal.
The room for this is kitten play chat, which runs both the soft and the bratty end at the same time.
Pony play terms
Pony. The person in the horse role. Pony play is the most formal branch, built around posture, discipline and performance rather than affection.
Groom. The handler equivalent. A groom cares for the pony, brushes, feeds, tacks up and manages them. The word carries service in it, not just authority.
Cart pony. A pony trained to pull. Strength, endurance and steady work.
Show pony. A pony trained to be looked at. Presentation, high stepping, being displayed and judged. The exhibitionist end of the discipline.
Riding pony. A pony trained to be mounted or led. Emphasis on control and trust.
Tack. The gear. Bridle, reins, harness, plume, hoof boots. Named directly from equestrian equipment.
Bit. The mouthpiece of a bridle. Removes speech, which for many ponies is the whole point of the role, since a pony that cannot talk communicates by posture instead.
Gaits. The trained ways of moving: walk, trot, canter. Learning and holding them is what pony training largely consists of.
Dressage. Precise trained movement performed to command. The most demanding form and the one that most resembles a discipline rather than a game.
All of it, in text, in pony play chat.
Words that move between rooms
Several terms here mean something else elsewhere, which is the main source of crossed wires. Collar means gear in a pup scene and commitment in a D/s one. Trainer means behavior coaching here and something quite different in chastity circles. Primal is an adjacent style, not a pet type. Alpha and omega are pack ranks, not the fiction genre. Little and pet are not interchangeable either, despite the overlap in tone, since a little is a person in a young headspace rather than an animal one.
For the broader vocabulary that pet play sits inside, the BDSM glossary covers the general terms, and if you know what role you want, find a handler and find a pet are the practical next steps rather than more reading.