Glossary of UK Caving Terms

If you're new to caving, some of the route descriptions you end up reading might sound like a different language. Caving terminology has been developed to help describe the various nightmares and adversities we experience underground, and hopefully the list below provides you with some ideas about the gibberish you encounter in guidebooks!

Some of these aren't 'official' terminology as such but might be regularly used in route descriptions and guidebooks, and we've tried to provide a useful rough idea of what these should be interpreted as.

We've omitted more scientific terms for formations, as well as equipment used, as there are plenty of glossaries available for these online - this list is primarily related to the sport of caving.

Abseil — Descend a fixed rope using friction (with a descender), typically down a pitch. See also: Rappel. 

Active — Describes a cave/passage that currently carries flowing water (a “live” streamway), as opposed to a fossil/dry passage. 

Anchor — A secure point used to attach a rope, ladder, cows-tail, or safety line (natural or artificial). 

Bedding Plane — The (often near-horizontal) boundary surface between rock layers; caves may develop along it, producing low, wide “bedding-plane” passages. 

Breakdown — Collapse debris (blocks/boulders) that has fallen from a cave roof or wall; may form a boulder choke.

Ceiling sucking — Slang for squeezing through a very low airspace above water (often in a duck) by keeping your face right up to the roof to “steal” what little air gap exists. 

Chamber — A noticeably enlarged area of passage, often at junctions or major enlargements. 

Chock stone — A rock wedged between walls (or roof/floor) in a rift/passage; sometimes used as a natural belay/anchor if truly solid.

Choke / Boulder choke — A section blocked or tightly filled with boulders (often breakdown), restricting or stopping progress.

Choss / Chossy — Loose, unstable, unpleasant rock (and “chossy” means “full of choss”).

Crawl — Low passage requiring movement on hands and knees, elbows, or belly.

Deviation — A rigging technique that pulls the rope away from a wall to avoid rub points (often using a sling/krab to an anchor). 

Dig / Digging — Excavating sediment, boulders, or constrictions to extend or reopen a cave route (“a dig”).

Doline — A closed surface depression in karst (a sinkhole), formed by solution and/or collapse. See also: Sinkhole/Sink.

Duck — A low section where water reaches the roof or nearly so, requiring you to lower your head (sometimes briefly submerge) to pass. 

Exchange — A planned trip where teams enter from different entrances (or using different routes) and effectively “swap” ends (often meeting mid-system); commonly used in multi-entrance pothole systems. 

Exposed — Airy or high-consequence ground (e.g., a traverse above a drop) where a slip would have serious consequences.

Fault — A fracture/zone of weakness in rock with movement; caves and passages can form along faults. 

Flat-out — A very low crawl done fully prone (on your front or back)

Fossil passage — An abandoned (usually dry) passage formed by an older water route, often left behind by lowering of the water table or stream capture.

Free-climb — Climb a pitch/climbable section without using a rope technique for ascent/descent (though it may still be protected with a handline depending on context). 

Free-dive — Breath-hold diving (no breathing apparatus), sometimes used to pass very short sumps by experienced cavers

Free-hanging — A rope hang where the rope does not touch the wall (a “free-hang/clean hang”). 

Grovel — Informal: awkward, low, undignified progress—often a nasty crawl/squeeze in mud or water.

Hading Rift — A rift passage that slopes (has “hade”) rather than being vertical; often an awkward, leaning fissure. 

In-situ — Left in place in the cave (e.g., fixed ropes/ladders/handlines or old slings). See also: Tat, Fixed aid. 

Karst — Landscape formed mainly by dissolution of soluble rock (especially limestone), typically featuring caves, sinkholes, sinking streams, and resurgences.

Maze Cave — A cave with many interconnecting passages and route choices (complex navigation). 

Oxbow — A bypass loop/offshoot passage (often a remnant of an older meander/route) that rejoins the main line later.

Phreatic — Formed below the water table where passages are water-filled; tends to produce more tube-like/rounded forms. 

Pitch — A vertical or near-vertical drop in a cave requiring a ladder/rope/SRT to descend (and sometimes ascend).

Pothole — a predominantly vertical cave system (often with multiple pitches), typically formed by stream capture into limestone. 

Prussik — Ascending a rope using ascenders (“prusiking”). 

Pull Through — A through-trip rigging approach where the rope is retrieved after everyone descends a pitch, so it can be reused on the next pitch (reducing the need to prusik back up). 

Rappel — Synonym for Abseil (common in US usage). 

Re-belay — Re-anchoring a rope partway down a pitch (often to avoid rub points or break a long drop into safer sections). 

Resurgence — Where an underground stream re-emerges to the surface (a spring). See also: Rising. 

Rift — A passage that is relatively high and narrow (fissure-like), often formed along joints/fissures. 

Rigging — Setting up ropes, anchors, and safety lines for pitches/traverses so the team can descend/ascend safely.

Rising — Synonym for Resurgence (a place where water “rises” back to the surface).

Sinkhole / Sink — A surface hollow in karst (often a doline). “Sink” can also mean a point where a stream sinks underground.

Shakehole — Synonym for a doline

Speleothem — “Cave formations”: secondary mineral deposits like stalactites, stalagmites, flowstone, etc.

Spit — A hammered-in, removable anchor (historically common for rigging); generally considered old-school and context dependent. 

Squeeze — A very tight section requiring awkward body positioning to pass (may be short and sharp or long and exhausting).

Sump — A water-filled section of passage that blocks a dry-air route; passable only by diving or when water levels drop enough to expose airspace. 

Swallet — A place where surface water sinks underground (a swallow hole), often the entrance point to an active stream cave. 

Tat — Old slings/rope left in place (often scrappy/unknown condition). Treat with caution. 

Through Trip — Enter one entrance and exit a different one (no need to return the way you came). 

Thrutch — To force your way through awkward/tight ground using whole-body shuffling, scraping, and heaving (often in rifts).

Traverse — Moving sideways across a wall/ledge above exposure, usually protected by a rope. 

Vadose — Formed above the water table where water flows with a free surface; commonly produces canyon/keyhole-shaped stream passages.