As in all sports, terminology has developed in rock climbing in order for us to more easily convey our ideas and stories to other climbers. It is easier to tell a climbing partner to 'pull on the arete, and then rock-over on the sharp crimp' than to say, 'pull on the edge there that resembles a sort of ridge, and then place your foot on that small protuberance of rock, transfer your weight over that foot, and now try and stand up'. Especially if they are halfway up the climb, and rapidly running out of strength! It is also vital for safety reasons to have a standard set of calls, so that climbers know when it is safe to climb, and know when to pay out rope and take in slack to minimise the risk involved.
This glossary is an attempt to gather the most commonly used terminology, and also to try and point out where this differs between the UK and the US (UK terminology is the default).
You are about to start climbing, so it's probably a good idea to choose something to climb. Here are a selection of climbing locations and rock angles - factors that will determine the style of climbing you will attempt.
Rock Angle and Size
Big Wall - Huge cliffs, found in places such as Yosemite and Norway's Troll Wall. These often take days to climb, with sleeping taking place on portable ledges.
Boulder - A small freestanding lump of rock. Often used as training for rock climbing, or for attempting hard climbs on without the fear of doing so many feet above the ground. Bouldering (climbing on boulders) has in fact become a sport in its own right.
Bulge - A protruding section of the climb, steeper than the main section. These can be awkward li'l devils.
Crag - An outcrop of rock. Found as small inland cliffs (eg the gritstone edges of the Peak District, or the limestone monstrosities of Yorkshire), sea cliffs (Wales, Dorset and Cornwall have some great examples of these) or as parts of larger mountain ranges (eg outcrops in Scotland, Wales and the Lake District).
Mountain Cliff - Altogether more serious, a mountain cliff will often resemble a few crags stacked one on top of the other. Usually more remote than crags, you'd better know what you are doing if something goes wrong.
Overhang - Anything steeper than vertical (though usually used in the same manner as 'roof').
Overlap - A small roof, usually between 9" and 2ft in depth.
Slab - A section of climbing which is less than vertical. Less strenuous than other angles, but often tenuous and scary.
Roof - Pretty self explanatory; a horizontal or near horizontal section of a climb, capping a gentler section. Strenuous.
Wall - A near vertical rock face.
Since your life may depend on it, it pays to look closely at the formation of the rock. Which features can the hands and feet actually use? Here is a fairly comprehensive list of rock formations:
Arete - An outside corner, resembling the edges of a brick on a grander scale (US - 'Corner').
Break - A horizontal crack.
Chimney - A fissure wide enough to fit the body in.
Chockstone - A rock or boulder wedged into a crack or chimney.
Corner - the opposite of an arete. Like the corner of a room (US - 'dihedral').
Crack - Usually refers to vertical fissures in the rock.
Crimp - Any very small hold which requires good finger strength to hold.
Flake - A layer of rock that appears to be on top of, but separate from, the base rock.
Groove - A shallow vertical opening, like an open crack without the fault in the rock.
Jug - A large hold. Americans call these 'buckets'. Think big...
Offwidth - A crack too wider than a fist, but narrower than your body...
Pinch - A protrusion of rock which is best used by pinching (qv).
Pocket - A hole or depression in the rock.
Pod - A short shallow break or crack.
Ramp - A diagonal ledge of any width.
Sidepull - A vertical hold, used by pulling from the side.
Sloper - Any hold which is made harder to hold by it being angled the wrong way. Imagine half a tennis ball being glued to the rock, and you'll have a fair idea of what a sloper may be.
Thread - A 'hole' through the rock. It can be used by wiggling the fingers into it, and is also often used for protection.
Undercling - An 'upside down' hold. May sound useless, but can be invaluable in making a high reach.
Note that combinations of these holds are possible, so we might have slopey crimps, a sidepull jug, or even a slopey, crimpy undercling.
Now that you know what the rock formations are, you need to know how to use them. There is a large array of techniques used in climbing, and many of these are aimed at specific types of hold or rock angle:
Bridging - Spanning between holds in a corner or chimney, usually with arms and legs akimbo (US - Stemming).
Dyno - Short for 'dynamic move', a dyno is literally a leap for a hold which is out of reach! Typically, both feet and at least one hand leave the rock, and the hold you are going for is generally large. Not used very often in climbing, due to its committing nature, though Johnny Dawes (probably the top climber of the 1980s) seemed to use it on nearly all his routes - including one where the dyno was in order to get a heel hook!
Edging - This is simply using the edge of the rock boot on small sharp edges.
Flagging - In order to get balanced in certain positions, particularly when the hand and foot holds are vertically in-line, or if you are having to stretch for a hold quite far away horizontally, then you may need to flag or stretch a leg out to act as either a counter balance, or as a third point of contact to create a balanced triangle.
Heelhook - Generally used on steep rock, and particularly when turning the lip of an overhang. This utilises a very high foot hold, which you place your heel on (often above your head), and then use the power in that leg to assist in hauling your mass up the rock. Turning the lip of an overhang, this is often used to get into a mantling position to get into a standing position on the lip.
Jamming - Using your hands as a camming device to use a (typically) vertical crack as a hand hold. The hand is inserted into the crack, and then either twisted to cam the fingers into the crack (finger locks), flexed to fit the crack (hand jams) or formed into a fist (fist jams). In the latter two cases, these can be very painful, as you are using the frictional properties of the back of the hand and front of the fingers to pull up on! If done properly, these can be very secure.
Layback - Using one side of a wide vertical crack for the hands, and the other side of the same crack for the feet, you can generate enough friction to stay on the rock. Laybacking is using this position to move up a crack (or other feature allowing the same sort of position). Strenuous, but less painful than jamming.
Mantle - Imagine you're getting out of a swimming pool, and you push down with your hands to lift yourself out of the water. That's essentially a mantle. Anything with this sort of pressing action is called a mantle.
Pinching - The opposite of spragging - literally pinch a hold between thumb and fingers.
Popping - A small dyno. Generally a semi-dynamic move where the hold is just too far to reach statically.
Rockover - A technique often used on slab climbs, a rockover is a way of making a high step to one side easier. Place your foot on the high hold, and then use any available hand holds to move your weight over and across that high foot hold.
Smearing - When there are no holds for the feet, but the texture of the rock is quite coarse, you can use the sole of your sticky rubber rock boots to make use of the available friction to stand on. Called smearing.
Splitting - This is a strenuous alternative to laybacking or jamming - the hands are used to try and pull the crack apart. Hard to keep moving on, as once you release one hand, the other loses the friction necessary to stay on the rock! It can be done though, in small dynamic bursts, or if the rock allows a sort of brief layback to alternate sides.
Spragging - A technique that can be used on cracks too small to get the fingers into, this is like splitting the crack with the thumb and fingers.
Undercutting - A technique using underclings. The undercling needs to be fairly low - preferably waist height or below - and is held in tension using the strength in the biceps. Think trying to pick a car up by the sill. As this works with one arm pointing toward the ground, holds a full arm span apart can often be linked.
OK. Now you know what the rock looks like, and how to use it. What's next? Well, unless you're into a spot of 'bare-naked bouldering', you'll want some equipment:
Belay Device - One of many devices used to control the rope. It is attached to the harness, and is used to lock off a rope in the event of a fall. Equivalent to holding the rope really, really hard, but better and less painful. Many shapes and sizes are available, from plain screw-gate krabs with an Italian hitch (special braking knot) to specially designed mechanical contraptions and even the climbers own body can be used as a belay device if one of a number of archaic and outdated methods are employed.
Chalk - Magnesium carbonate, in powder or block form, stolen from gymnasts to reduce sweat on the hands, and so increase chances of staying on the rock.
Harness - A nylon contraption which sits around the hips and thighs, that you can theoretically hang from a rope on indefinitely.
Karabiner - A C-shaped piece of aluminium, with a gate across the opening of the 'C'. Used as a link between protection, slings and ropes. These come in various styles, but all can be classified as either a snap-gate krab, where the gate is held shut with a spring, or locking-gate krab, where the sprung gate is additionally locked off with a screw, or some other safety device.
Protection - Bits and pieces of ironmongery designed to be placed in cracks and faults in the rock. These take the shape of different sized wedges of aluminium on wire or nylon cord (known as rocks/nuts/wires/wedges for the smaller sizes, and hexes for larger sizes), nylon slings, friends (devices which can fit a range of sized cracks by using pairs of opposing cams), and other more esoteric devices.
Quickdraw - Nothing to do with the Wild West, these devices are a length of nylon sling, with a karabiner at each end. Used as a link between the rope and protection.
Rock Boots - Tightly fitting shoes, with sticky rubber soles. Designed with discomfort in mind. The idea being that you are so desperate to get the damned things off, that you will find hidden reserves of strength in order to reach the top!
Runner - The generic name for the combination of a quickdraw linking a piece of protection in the rock with the rope. Short for 'running belay'.
Now you have all of the ingredients to start climbing - some rock, some techniques and some equipment, it's time to put it all together and learn how to stop yourself and your partner from having too bad an accident.
Belay (noun) - A setup of a climber and at least one, but preferably three, pieces of protection in the rock, linked together with a bird's nest of rope and slings, from which the climber (usually standing on a good ledge, but occasionally dangling from the nest by the harness aka hanging belay).
Belay (verb) - Belaying is the act of controlling the rope using a belay device. Typically, the belayer pays rope out and takes rope in when required, and brakes the rope in the event of a fall.
Belayer - The person doing the belaying.
Climb - A route up the rock, often following an obvious line (eg. a crack or a corner), but often just following a series of good holds up an otherwise blank piece of rock.
Leader - The person on the 'sharp' end of the rope, climbing first, and placing and clipping into protection along the way.
Pitch - A section of a climb, chosen to be less than a rope's length in height (a typical rope is 50m), and preferably starting and finishing at good belays.
Second - The 'second' person up the climb, who removes any protection the leader has placed.