Lexical Definition

‎διθάλασσος‎ dithálassos (dee-thal'-as-sos) sandbar ^G:A
from ‎δίς‎ and ‎θάλασσα‎

where two seas meet.

• having two seas, i.e. a sound with a double outlet

Abbott-Smith

*† διθάλασσος, -ον (δις, θύλασσα);
1. divided into two seas (as the Euxine, Strab., ii, 522).
2. dividing the sea: τόπον δ., a tongue of land, or reef, running out into the sea: Ac 27:41.†

Abbott-Smith References

Liddell-Scott-Jones

διθάλασσος-θάλασσος,

Attic dialect διθάλαττος [θᾰ], ον, divided into two seas, of the Euxine, [Refs 1st c.BC+]; of the Atlantic, [Refs 1st c.BC+]

__II between two seas, where two seas meet, as is often the case off a headland, [NT]; βραχέα καὶ διθάλαττα shallows and meetings of currents, in the Syrtes, [Refs 1st c.AD+]

_{LSJ Scripture Refs: Acts.27.41}