Aquatic

Aquatic is the secret language used by SeaWings to communicate in the Deep Palace (or anywhere underwater) where they can't communicate clearly without going to the surface to talk. Instead of spoken words, Aquatic uses a series of talon gestures and the flashing of the bioluminescent stripes along the dragon's body (similar to sign language). Because only SeaWings possess these stripes, the language is not spoken by dragons from any other tribe. Tsunami is a rare case of a SeaWing who does not understand Aquatic very well at all, courtesy of being raised in a cave by the Talons of Peace. Webs didn't teach Tsunami Aquatic, possibly because he didn't think she would escape with the other dragonets. Riptide and Anemone taught her some Aquatic when she came to the Sea Kingdom. The way Whirlpool taught Aquatic to Tsunami was by having her copy Whirlpool by lighting up her bioluminescent stripes. The way Riptide taught Tsunami was by showing her simple words and phrases and having her copy them.

“Not right now, we’ll finish this later.”

Riptide teaching Tsunami basic Aquatic

Whirlpool's Aquatic lesson

Tsunami saying "I will protect" in aquatic.

In Talons of Power, a story was also mentioned of a dragonet who had been raised by orcas and didn't know Aquatic.

• Making a circle with index claw - "Not right now, we'll finish this later."
• An un-described claw gesture - "Inform the Queen."
• Three flashes on the tail stripes - "Squid-brain."
• Snout stripes - questions (who, what, where, when, why, or how).
• Stripes along the dragon's side and talon gestures - "I will protect."
• Some tiny stripes on the snout - "Hello."
• Spreading webbed claws - "I don't know."
• Pointing and stripes on the side - "All right?"
• A stripe on wings (speculated royal pattern only) - "Silence."
• Stripes on the sides of the body flashed twice fast - "Shut up!"
• Scales flashing along part of wings - "Why are you acting like an indecisive jellyfish right now?"
• Scales underwing - "She/He said to meet him/her at the sunset beach of the Island Palace"
• Scales underwing - "I'm sorry."
• Flashing stripes from snout to tail made accidentally by Tsunami while trying to tell Riptide she was a SeaWing- "Hey, sparkling teeth, I totally love three of your claws but not the others, and I wish your nose was a herring so I could eat it and also your wings sound like sharks snoring."
• Some tiny stripes on the snout - "I love my/our egg."
• Some tiny stripes on the snout - "Love." 

References

fr:Aquatic