Angulation = refers to the angles formed by bones of the limbs with respect to themselves and with respect to the ground.
Amble = a four-beat gait which is essentially an accelerated walk (preferred by elephants and some horses; only a transition gait in the dog).
Beats = the number of ground impacts during a stride (number of "hoof-beats" one might hear during a stride), e.g., if two legs simultaneously impact the ground & then the other two impact simultaeously, the gait is two-beat (trot or pace).
Canter = a three-beat gait, often used for non-strenuous, playful locomotion; involves rear limb, diagonal, and front limb supports.
Clipping = the back feet striking the front feet during a gait.
Contralateral = the opposite (left/right) side. Contralateral fore and hind limbs constitute a diagonal, as seen in the trot and other gaits.
Coupling = the body length between thoracic limbs and the pelvic limbs.
Crab-running = animal moving side-wise (crab-like) with its body at an angle to the line of progress. (Employed to avoid interference because it allows a hind paw to step past a fore paw without clipping it.)
Cursorial = adapted for running. All of the common domestic mammals are cursorial quadrupeds (four limbs used for locomotion).
Cycle (stride cycle) = sequence of movements that limbs undergo during one stride; movements a limb undergoes in returning to its original position. [To the left, phases of the step cycle that a paw undergoes are illustrated.]
Diagonal = combined use of a fore limb and contralateral hind limb to support body weight (the fore limb determines which diagonal is being employed, right or left).
Equilibrium = condition in which forces are balanced; condition of stability.
Extension = a joint motion that moves the connected parts further apart (increases the angle formed by articulating bones).
Fetlock = the joint between the cannon bone and the long pastern bone (metacarpal-phalangeal joint); the region of the fetlock joint.
Flexion = the motion of a joint that brings the connected parts closer together (decreases the angle formed by articulating bones).
Flying trot = a two-beat gait involving alternate diagonals, identical to the normal trot except for a suspension phase between each diagonal support.
Gait = a particular sequence of limb movements repeated to produce locomotion, e.g., walk, trot, pace, canter, gallop, etc.
Gallop = a four-beat gait that features suspension phase(s); also, the fastest gait. Two types of gallop exist (see: Transverse gallop and Rotatory gallop).
Inertia = the property of a body to maintain a state of rest or uniform linear motion unless acted upon by external force.
Interference = when a rear paw strikes the ipsilateral fore paw because the fore paw is not removed from the path of the rear paw, as it should be.
Ipsilateral = the same side, as opposed to contralateral.
Lead (leading limb) = the fore limb that is not part of the diagonal (canter); the fore limb that's in contact with the ground just before suspension (gallop).
Long striding walk = a type of walk in which the hind limbs impact ahead of the site of forelimb impact.
Momentum = the product of mass times velocity; generated by limb thrust (work) during locomotion.
Pace = a two-beat gait that features sagittal support (combined use of ipsilateral fore and hind limbs); employed instead of the trot by some animals.
Power walk = the type of walk used by animals pulling a load; steps are shorter and slower than in a normal walk, and sagittal support is minimized.
Rack = pace (see: Pace ).
Rotatory gallop = a four-beat gait of carnivores, swine, rodents, and small ungulates that features trunk flexion/extension and two suspension phases; a suspension phase occurs after the second-landing hind limb is lifted, as well as after the second-landing (leading) fore limb is lifted.
Sagittal = a plane or direction parallel to the long axis (median plane) of the body; sagittal support involves ipsilateral as opposed to diagonal limbs.
Sequence = the series of (four) steps comprising a single stride (of any gait).
Side-stepping = a synonym for crab-running (see: Crab-running).
Side support = sagittal support; combined support by ipsilateral fore and hind limbs.
Sight-hound = a breed that runs (courses) game by sight rather than scent.
Step = one limb undertaking one cycle in a stride (cycle = lift, swing, support, thrust).
Stride = a unit of locomotion during which all limbs each complete one step (at the completion of a stride, limbs have the same relative positions as when they started); also, Stride = stride length = the linear distance between two successive ground impacts of the same foot.
Suspension = phase of locomotion during which no limb is touching the ground (supporting the trunk).
Sustained gallop = the canter (see Canter).
Transverse gallop = a four-beat gait with support phases like the canter, except that the diagonal is split (hind paw lands before the fore paw) and a suspension phase occurs after the leading fore limb leaves the ground.
Trot = a two-beat gait that uses only diagonals for support, used for traveling long distances at a fair rate of speed.
Walk = a four-beat gait in which all legs step sequentially, used for leisurely travel.
