great sea turtle
鼇 refers to a great sea turtle, a large mythical or real marine turtle.
鼇 combines 敖 (phonetic, possibly suggesting large or proud) with 黽 (a frog or turtle-like creature), indicating a large turtle. The exact historical development is uncertain.
The top part 敖 looks like a proud chief, and the bottom 黽 is a turtle. Imagine a proud, giant sea turtle rising from the waves.
For ゴウ, picture a great sea turtle named 'Gou' (ゴウ) swimming mightily through the ocean.
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