RhymeZone: laplace operator definitions

Definitions of Laplace operator:

noun: (mathematics, physics) A differential operator,denoted ∆ and defined on ℝⁿ as 𝛥=∑ᵢ₌₁ⁿ(∂²)/(∂x_i²), used in the modeling of wave propagation, heat flow and many other applications.

(Definitions from Wiktionary)