n.; pl. Deltas [ Gr. de`lta, the name of the fourth letter of the Greek alphabet (the capital form of which is Δ, Eng. D), from the Phœnician name of the corresponding letter. The Greeks called the alluvial deposit at the mouth of the Nile, from its shape, the Delta of the Nile. ] 1. The fourth letter of the Greek alphabet (Δ δ), corresponding to D. Hence, an object having the shape of the capital Δ. [ Webster 1913 Suppl. ]

2. A tract of land shaped like the letter delta (Δ), especially when the land is alluvial and inclosed between two or more mouths of a river; as, the delta of the Ganges, of the Nile, or of the Mississippi. [ 1913 Webster ]

3. (Elec.) The closed figure produced by connecting three coils or circuits successively, end for end, esp. in a three-phase system; -- often used attributively, as delta winding, delta connection (which see), etc. [ Webster 1913 Suppl. ]

. (Elec.) One of the usual forms or methods for connecting apparatus to a three-phase circuit, the three corners of the delta or triangle, as diagrammatically represented, being connected to the three wires of the supply circuit. [ Webster 1913 Suppl. ]

. (Elec.) The current flowing through a delta connection. [ Webster 1913 Suppl. ]

n. [ Delta + L. facere to make. ] The formation of a delta or of deltas. [ R. ] [ 1913 Webster ]

a. Relating to, or like, a delta. [ 1913 Webster ]