Ryuu.
or you can use Tatsu as well,
The Japanese word for Dragon is "Ryuu"
Doragonfurūtsu
ドラゴンストライキ
ryu no ha
Doragon iki
Kagami Ryū
'Kinzoku no ryuu'.
ginryu
ryu-ken
to say dragon in Japanese is 龍 and it is read ryuu hope this helps :)
'Small dragon' would be 小さい竜 (chiisai ryuu) in Japanese.
well... oean means umi, and ryuu means dragon