Akademik

turn turtle
verb
a) To turn upside down. Commonly used for boats and ships that capsize and turn through 180° so their hulls are above their superstructure, but it can refer to any vehicle in a similar position.

1998: a surfer prepares to turn turtle in the righthand shot — Kite Aerial Photography [

b) To roll upside-down with ones surfboard (usually a longboard) to allow a wave (usually an already broken wave) to pass over.
Syn: upside down, eskimo roll
See Also: duck dive

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