The words of the water.

Holding your breath underwater. Much safer when done calmly, never alone, and never after over-breathing.

A trained partner who watches you in the water and can help you.

Proof from PADI or MFI that you completed a course and met its standards. Discover Mermaid is an experience, without one.

The wave-like movement, from the chest through the hips to the fin, that moves a mermaid forward.

Letting air into the middle ear to balance the water pressure as you go down. See Equalising your ears.

A light tail made of swimwear fabric over a monofin. Easy to put on; most people learn in one.

Diving on a single breath, without breathing equipment.

Breathing faster or deeper than you need, which delays the warning to breathe. Never do it before a breath-hold. See Breath-holding and shallow-water blackout.

Leggings worn under a tail or for land training, made for the movement of mermaid swimming.

Swimming with the legs held together in a tail, as a sport, an art or for fun.

The mermaid and underwater dance training organisation behind the M and D courses.

A single fin that holds both feet, so the legs kick together. The working part of a mermaid tail.

The breath-hold rule for two: one stays at the surface watching while the other dives.

The world's best-known diver training organisation, which also certifies mermaids.

Bringing a tired or unresponsive swimmer to the edge, keeping their face out of the water.

A planned sequence of movements and poses performed underwater, often to music.

Losing consciousness underwater from low oxygen, often without any warning and often near the surface.

A heavy, made-to-measure tail that looks real on camera. For experienced mermaids and performers.

Coming up for air calmly and smoothly, without rushing.

The fabric or silicone cover that goes over the legs and the monofin and makes the tail look like a mermaid's.