Rat Terminology
Here’s a list of common terms rat owners use:
Allogroom: One rat grooms the other, frequently around the neck or head.
Altricial: Being helpless, blind, and hairless at birth.
Barbering: Excessive grooming in which the fur is nibbled off.
Behavioral Estrus: Phase of the female rat's ovarian cycle during which she displays reproductive behavior.
Belly-Up Roll (Pin): Juvenile-type defense tactic in which one rat rolls onto his back before another, sometimes after receiving a nip or bite on the rump.
Bite: Piercing contact with the teeth that scratches or breaks the skin.
Boogling: The eyes vibrate rapidly in and out of the eye socket (often with bruxing)
Bound (Ricocheting Jump): Rat advances with leaps: it pushes off with both hind feet, lands on both front feet, brings forward the hind feet and pushes off again.
Boxing: Two rats stand on their hind legs face to face and nearly nose to nose, and push or paw at each other with their front legs and paws, usually around the head, neck, shoulders and front legs of their opponent. In high intensity boxing the rats stand erect on their hind feet and rapidly push, paw, and grab at each other. In low intensity boxing the rats squat on their haunches and paw at each other gently.
Bruxing: Grinding teeth (often accompanied by boggling), which rats do when very relaxed and happy or when nervous.
Buck: Male rat.
Buck Grease: patches of yellow or orange skin on the back of a mature buck.
Chatter: Repetitive grinding of the incisors against each other.
Communal Nesting: Two or more females combine their litters in a single nest and raise them together.
Communal Nursing: The sharing of milk with the young of another mother.
Dorsal Immobility: Freezing or "going limp" behavior that occurs when rats are picked up by the scruff of the neck.
Doe: Female rat.
Dominant: The rat who is "in charge," the "alpha" rat
Dumbo: Variety of rat that has large ears placed more on the side than the top of the head.
Ear Wiggle: Female vibrates her ears rapidly, usually displayed during behavioural estrus.
Fight or Wrestle: This is an escalated form of conflict, in which two rats wrap around each other into a tight ball, rolling around together and biting, frequently shrieking.
Flank Marking: Flank marking is a scent marking behavior involved in olfactory communication, in which scent from the flank is rubbed onto objects in the environment.
Forequarter Pivot: Adult defense tactic, in which the defending rat stands on its hind legs and pivots its forequarters to face the attacker, but leaves its hindquarters in contact with the ground.
Gallop: limbs of both sides move nearly in synchrony.
Head Bob (Sway): Movement of the head up and down or side to side in order to focus and gain a sense of visual depth.
Head Tilt: A condition in which a rat's head is tilted at an angle (not swaying, which is normal behavior for focusing). Usually caused by an upper respiratory/sinus/ear infection.
Heat: The period of time when a female is receptive to a male and can become pregnant.
Hiss: Vocalization made during escalated antagonistic encounters, typically when rats are very close to or in contact with each other.
Litter: (1) The offspring born to one mother at one time. (2) The substrate used in a litterbox or in the bottom of a cage to control moisture and odor.
Lordosis: Female mating posture. Female stands immobile, with her back arched downward toward the floor, her rump pushed upward and tail deflected to the side.
Marking: The rat deposits tiny droplets of urine on the surfaces and objects he walks on.
Mounting: Engaging in "mock mating," done by both genders in play or dominance.
Myco: Short for Mycoplasma Pulmonis, a bacterial infection all pet rats carry, but most do not show symptoms unless they are stressed, old, or have another infection.
Nestbuild: Rats may drag or carry desirable nesting material in their mouths into their chosen sleeping spot, such as a nestbox or burrow.
Nibble: Rats may nibble their own skin or that of other rats with their teeth.
Nip: Light pinching contact with the teeth, skin unbroken. May elicit a squeak.
Nose-off: Two rats stand immobile, facing each other.
Nursing Posture: Huddled, crouching posture of a mother rat over her offspring, which allows them to nurse and provides them with protection and warmth.
Nocturnal: Being most active at night.
Odd-eyed: Having two different colored eyes (like one red and one black or one pink and one red).
Open-Mouth Tooth Display: Facial expression in which the mouth is open, revealing the base or all of the bottom incisors. In a very intense version, the mouth is wide open and lower incisors are spread apart into a "V" shape, and the rat may squeak or hiss.
Overmark: Deposit of a scent mark over the scent mark of another rat
PED: Abbreviation for pink eye dilution, a gene that results in champagne rats, pink-eyed fawns, and silvers.
Pica: The consumption of non-nutritive substances like clay, kaolin (a type of clay), or even bedding. Pica is the rat's response to nausea, as rats cannot vomit.
Piloerection: The rat's body hair stands on end when the rat is cold, or when stressed, such as during or after an intense altercation.
Pinkies: Newborn rats before their fur grows in.
Poryphin: The red discharge that comes from a rat's eyes and nose when he is sick, stressed, or has an allergy or sensitivity to something.
Postpartum Estrus: The heat cycle rats go into immediately after giving birth.
Power Grooming: when one rat grooms another often or with excessively force.
Pup: Baby rat.
Pup Retrieval: Carrying behavior in which a mother rat picks up a straying pup in her mouth, usually by the neck, and brings it back to the nest.
Rat, fancy: Rats bred specifically to follow set standards and to be good pets.
Rat, feeder: Rats bred and/or sold for the purpose of being food for another animal.
Rat, Norway: Any rat of the species Rattus norvegicus. Usually is used only to describe the wild rats, not their domesticated counterparts.
Rat, pet: Any domestic rat being kept as a pet.
RED: Abbreviation for red eye dilute, the gene that causes beige, fawn, platinum, and other dark ruby-eyed colors..
Rex: Rats with curly or wavy fur and whiskers.
SDA: Abbreviation for the Sialodacryoadenitis Virus, a highly contageous (to rats) upper respiratory infection that causes swelling of the throat and eye problems. SDA is not fatal, but allows for myco and other secondary infections to flare up and possibly kill.
Sendai: A contageous virus that affects rats and mice and is similar to distemper.
Shriek: Loud scream that covers many frequencies at once, from 0.2 to 20 kHz and perhaps up into ultrasound. Heard during fights, or when rat is in pain, or in strong protest.
Sidle: Threatening posture in which one rat approaches another rat sideways or broadside ("crab walks"), with his back strongly arched, and crowds the second rat.
Social biting: In a social context, rats may bite each other, particularly during fights. Offensive bites tend to be directed at the lower back and flanks. Defensive bites tend to be directed at the face. Defensive bites are sometimes delivered in a lunge-and-bite sequence. The bite to the head is characteristic of hurt, frightened, or defensive rats.
Solicitation: Female initiation of sexual interaction. A female rat in behavioral estrus will attempt to initiate and maintain mounting behavior by soliciting the male. She darts towards him, then runs or hops a short distance away. She may wait a bit, move back, wiggle her ears, and repeat the sequence.
Sphynx: Hairless rats.
Stash: The rat picks up a food item in its mouth, runs elsewhere, and deposits the food item
Stud: A male rat that a breeder borrows for breeding.
Tail Wagging: Tail moves sinuously on the ground, and may bang on the floor. The movement may involve the entire tail, or as little as the tail tip.
Tonic Immobility: Freezing behavior seen when pressure is applied to the upper back/nape of a rat.
Trot: Gait in which legs within the girdles step in alternation.
