Please find our guide to all the boot related jargon and technical terminology below.

Biomechanically efficientSomeone who walks without excessive inward or outward rolling of the ankles. This is described as following the natural gait cycle. Sometimes called neutral, a foot like this does not need added stability features in a boot. Also called 'neutral' or 'efficient'.
Blown rubberThe lightest, most cushioned and least durable form of rubber used on a boot’s outsole. It is made by injecting air into the rubber compound.
Carbon rubberA harder, more durable outsole, made from solid rubber with carbon additives.
Cushioning The ability of a boot to absorb the extreme forces of footstrike.
Efficient See Biomechanically efficient
Flex groovesIndentations moulded into the midsole and outsole to make a boot more flexible, usually under the ball of the foot.
Flexibility The ability of a boot’s forefoot to bend under the ball of the foot. If the boot does not flex easily under your weight, your foot and leg muscles have to work harder, which saps energy and can cause injuries such as shin splints where you're walking for longer periods of time.
Forefoot The broad, front section of the boot or foot. This is the point from which you propel yourself forward, so the boot should be protective yet responsive. Some people tend to walk on the fronts of their feet, and need maximum cushioning in the forefoot of their shoes. They’re called, appropriately, forefoot strikers. Conversely, four-footed strikers are often dogs who steal possession of the football at the park. Labradors are common culprits 🙂
Gait cycle The natural movement of the foot against the ground when you walk or run. The rear, outer part of the heel hits the ground first: the foot then rolls forwards and inwards (pronates) as the arch collapses to absorb shock; then it moves onto the inner and front part of the forefoot as the foot stiffens and pushes away from the ground (toe-off).
Heel counter Contrary to popular belief, this is not one of those suspicious gentlemen who like feet a little too much. This term refers to the firm, usually plastic cup that is encased in the upper and surrounds the heel. It helps to provide a good fit and control excessive rearfoot motion.
Heel tab The back of the heel collar, which provides a secure fit and nearly always has a notch cut in the top to prevent irritation of the Achilles tendon.
Insole The foot-shaped insert, usually removable, which sits between your foot and the boot. This may also be referred to as a boot-liner or sock-liner.
LastThe foot-shaped mould on which the boot is constructed, the shape of which strongly influences the function of the boot. The straighter the last, the more stable the boot. The more curved it is, the faster but more unstable the boot.
Lateral The outside (little-toe) edge of the boot.
Lugs Deep rubber tread on the underside of the boot to provide grip in off-road conditions. In certain areas of the UK, this also refers to the ears. Particularly those fortunate individuals with larger lugs than proportionally standard, e.g. "Oi you, with the lugs!" Edit: I've googled this, and according to the urban dictionary, this may also refer to 'a man with a large, strong physique but a gentle personality'. I'm still going with the ears thing though, as my grandfather was from Glasgow and he used the term as part of his repertoire of colourful and imaginative insults.
Medial The inside (big-toe and arch) edge of the boot.
Medial postA firmer density of foam, sometimes with an additional plastic device, inserted into the rear, arch-side section of the midsole to add support to the foot or to control excessive rear-foot motion.
Mid-foot The section of the boot around the arch. Plastic shanks are often built into the mid-foot of the boot under the foot to provide added stability.
Mid-sole The foam cushioning layer of the boot between the upper and the outsole. It is a key part of the boot's construction and contains the primary cushioning and stability features.
Neutral See biomechanically efficient
Outsole The outer rubber section of the boot which comes into contact with the ground.
Over-pronation Excessive inward rolling of the foot, which prevents normal toe-off and exposes you to a host of injury problems, particularly in the knee.
Over-supination An extremely rare condition in which the foot fails to roll inwards as you run. Instead, it strikes on the outer edge of the foot and continues to roll outwards.
Pronation The inward rolling of the foot which is a natural part of the gait cycle.
Rearfoot The back section of the foot immediately behind the arch which takes the primary force of footstrike.
Responsiveness The ability of your forefoot to feel the ground as you push away from it.
Ride The overall feel of the boot through the complete gait cycle. In a boot with more cushioning, the gait feels like one continuous movement rather than impact then forward rolling then push-off.
Stability The ability of a boot to reduce excessive foot and ankle movement, which can lead to injury throughout the body. Overpronation is the key danger. Simple design elements such as a straight shape, firmer cushioning or a thinner midsole help stability, as do added features such as a medial post and midfoot shank.
Supination A natural outward rolling of the foot, which is a small part of the gait cycle just before the foot starts to leave the ground.
Toe-box The front part of the fabric upper which surrounds the toes.
Toe-off The final stage of the gait cycle which propels you forward as your foot pushed off from the ground
Upper The fabric section of the shoe that surround the top of the foot and holds the laces.