This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
鷔 combines 敖 (top) and 鳥 (bird). The exact historical development is uncertain, but it likely represents a type of bird, possibly related to the flying fish reading とびうお.
A bird (鳥) with a complex top (敖) that might suggest a proud or soaring bird, but its meaning is uncertain.
For ゴウ, imagine a proud bird letting out a loud 'gou' call as it soars: gou -> ゴウ.