The vaping glossary: every term you will meet, in plain English

• 510 connection: the standard screw thread that lets most tanks fit most mods.
• 18650: a common rechargeable battery size, 18mm wide and 65mm long, used in many mods.
• AIO (all-in-one): a device with the battery and tank built into one body.
• Airflow: the holes or slider that let air in. Closed is tighter, open is airier.
• Atomiser: the part that turns liquid into vapour. Tanks and pods are atomisers.
• Auto-draw: a device that fires when you inhale rather than when you press a button.
• Battery capacity (mAh): how much charge a battery holds. Higher usually lasts longer.
• Big puff kit: a prefilled kit with a large refill container, sold on a high puff count.
• Bottom fill: a tank filled from underneath, usually by unscrewing the base.

• Chain vaping: taking puffs back to back with no break. A fast route to burnt hits.
• Ceramic coil: a coil that uses a porous ceramic core instead of cotton.
• Cloud chasing: vaping for the biggest possible clouds, usually on very low-ohm coils.
• Coil: the heating element, a metal wire or mesh wrapped in cotton.
• Coil head: a replaceable, ready-made coil that screws or pushes into a tank.
• Concentrate: strong flavouring for mixing your own liquid, never vaped neat.
• Contacts: the metal points where the pod or coil touches the battery.
• Cotton: the wick inside a coil that soaks up liquid.
• Cut-off: the safety timer that stops a device firing after a set number of seconds.

If one term on this list matters most for a beginner, it is the coil, because almost every taste problem traces back to it.

• Disposable: a single-use vape. Banned from sale in the UK since 1 June 2025.
• DIY: mixing your own liquid from a base, concentrate and nicotine.
• Drip tip: the mouthpiece on a tank. Usually swappable.
• Dry hit: a harsh, burnt puff caused by a coil with no liquid on its cotton.
• DTL (direct-to-lung): inhaling straight into the lungs in one breath, like a deep sigh in reverse.
• E-liquid: the liquid you vape, made of PG, VG, flavouring and usually nicotine.
• Fill port: the hole or slot you fill a pod or tank through.
• Flavour fatigue: when your favourite flavour starts tasting of nothing. Also called vaper's tongue.
• Freebase: nicotine in its original form, with a sharper throat hit than nic salts.

Dry hit and flavour fatigue are the two you will feel first, usually in the same week.

• Gunk: dark residue that builds up on a coil, mostly from sweeteners.
• Hybrid nic: a liquid that mixes freebase and salt nicotine.
• Juice: everyday slang for e-liquid.
• Kanthal: a common coil wire, an iron-chromium-aluminium alloy.
• Leaking: liquid escaping the pod or tank, usually from overfilling, a worn seal or a hard draw.
• Mesh coil: a coil made from a flat metal mesh instead of round wire, heating more evenly.
• Mod: the battery part of a tank setup, often with a screen and power settings.
• MTL (mouth-to-lung): drawing vapour into your mouth first, then breathing it in, like a cigarette.
• Multipack: several 10ml bottles of the same liquid sold together.

MTL and DTL come up constantly. Our MTL vs DTL guide explains the difference properly.

• Nic salt: nicotine bound to a mild acid, making high strengths smoother.
• Nic shot: a 10ml bottle of plain nicotine, usually 18mg, for adding to shortfills.
• Nicotine strength (mg): milligrams of nicotine per ml of liquid. UK maximum is 20mg.
• Ohm: the unit of coil resistance. Below 1.0 ohm is called sub-ohm.
• Ohm's law: the maths linking volts, amps and ohms. Power in watts equals volts squared divided by ohms.
• PG (propylene glycol): the thinner base liquid. Carries flavour and throat hit.
• Pod: a small plastic tank, usually 2ml, that clips into a pod kit.
• Priming: soaking a new coil with liquid before the first puff.
• Puff count: a maker's estimate of puffs per pod or kit. A guide, not a promise.

Try the calculator to see Ohm's law in action.

• RDA: rebuildable dripping atomiser. You build the coil and drip liquid straight onto it.
• RTA: rebuildable tank atomiser. You build the coil, and it has a tank.
• RDTL: restricted direct-to-lung. A direct inhale with some airflow resistance.
• Resistance: how much a coil resists current, measured in ohms.
• Shortfill: a nicotine-free bottle, often 50ml or 100ml, left part empty so you can add nic shots.
• Spit back: tiny drops of hot liquid popping up the mouthpiece.
• Steeping: letting a freshly mixed liquid rest so the flavours blend.
• Sub-ohm: vaping on a coil below 1.0 ohm, usually DTL with big clouds.
• Sweetener: sugar substitute such as sucralose in many liquids. Tasty, but hard on coils.

• Tank: a refillable liquid chamber, usually glass, that holds a replaceable coil head.
• Throat hit: the catch at the back of your throat on inhale, driven by nicotine and PG.
• Top fill: a pod or tank you fill from the top. Most modern ones are.
• TPD: the EU Tobacco Products Directive, the origin of UK vape limits.
• TRPR: the Tobacco and Related Products Regulations 2016, the UK law that sets the 20mg, 2ml and 10ml limits.
• VG (vegetable glycerine): the thicker, sweeter base liquid that makes clouds.
• Wattage: power sent to the coil. More watts, more heat.
• Wick: the material, usually cotton, that carries liquid to the coil.
• Zero nic (0mg): liquid with no nicotine at all.

If nic salt versus freebase is still fuzzy, our nic salts guide clears it up.