∆

See also: △ and Δ

∆ U+2206, ∆ INCREMENT ← ∅ [U+2205] Mathematical Operators ∇ → [U+2207]

Translingual

Etymology

From the Ancient Greek capital letter Δ.

Symbol

∆

1. (mathematics) An increment or change in a variable.

   ∆x   the change in variable x

2. (set theory) The symmetric difference symbol.
3. (mathematics, physics) The Laplace operator.

   Synonym: ∇²

Usage notes

• Although this is the official encoding for the mathematical character, most math publications that apply Unicode (LaTeX publications rarely use Unicode) use simply the Greek letter Δ for convenience.

Synonyms

• Δ

English

Etymology

From translingual ∆ (“change”).

Noun

∆ (plural ∆s)

1. (Reddit) An award given to someone who successfully convinces someone to change their viewpoint.
   • 2025 April, “Can AI Change Your View? Evidence from a Large-Scale Online Field Experiment”, in University of Zurich‎^[1], pages 2, 5:

     In Figure 3, we report the fraction of comments that received a ∆ for each treatment condition. […] Meanwhile, ∆s can be awarded to any type of comment, without restrictions.