noun
delta
The fourth letter of the Greek alphabet.
The student writes a capital delta beside the lowercase letter.
Etymology
Greek delta inherited its name from the older Semitic letter-name associated with a door. Greek adapted that alphabetic sign and retained it as the fourth letter.
More examples
- A capital delta looks like a triangle.
- In this equation, delta represents a change in temperature.
- The Greek alphabet begins with alpha, beta, gamma, and delta.
Forms
delta · deltas