delta.

1. A landform built from sediment deposited where a river enters a larger body of water, often divided by distributary channels.

2. The fourth letter of the Greek alphabet, written Δ or δ.

3. A change or difference in a quantity, often represented by the Greek letter delta.

Use it for

Words that belong together

• a river delta
• delta channels

On the page

Delta channels shifted between the surveys, leaving the old landing inland.

The river delta spread into a mosaic of water and cultivated ground.

Usage notes

Primary category: setting. Forms: Singular delta; plural deltas. Legacy lexical fields mirror sense 1 only. Use numbered sense fields for all meanings.