Several concepts from mathematics and physics are named after the mathematician and astronomer Joseph-Louis Lagrange, as are a crater on the Moon and a street in Paris.

• Lagrangian analysis
• Lagrangian coordinates
• Lagrangian derivative
• Lagrangian drifter
• Lagrangian foliation
• Lagrangian Grassmannian
• Lagrangian intersection Floer homology
• Lagrangian mechanics
  • Relativistic Lagrangian mechanics
• Lagrangian (field theory)
• Lagrangian system
• Lagrangian mixing
• Lagrangian point
• Lagrangian relaxation
• Lagrangian submanifold
• Lagrangian subspace
• Nonlocal Lagrangian
• Proca lagrangian
• Special Lagrangian submanifold

• Euler–Lagrange equation
• Green–Lagrange strain
• Lagrange bracket
• Lagrange–Bürmann formula
• Lagrange–d'Alembert principle
• Lagrange error bound
• Lagrange form
• Lagrange form of the remainder
• Lagrange interpolation
• Lagrange invariant
• Lagrange inversion theorem
• Lagrange multiplier
  • Augmented Lagrangian method
• Lagrange number
• Lagrange point colonization
• Lagrange polynomial
• Lagrange property
• Lagrange reversion theorem
• Lagrange resolvent
• Lagrange spectrum
• Lagrange stability
• Lagrange stream function
• Lagrange top
• Lagrange−Sylvester interpolation

• Lagrange's approximation theorem
• Lagrange's formula
• Lagrange's identity
• Lagrange's identity (boundary value problem)
• Lagrange's mean value theorem
• Lagrange's notation
• Lagrange's theorem (group theory)
• Lagrange's theorem (number theory)
• Lagrange's four-square theorem
• Lagrange's trigonometric identities

• Lagrange point colonization
• Lagrange (crater)
• Lagrange Island, Antarctica
• Lagrange Island (Australia)
• Rue Lagrange, a street in Paris
• Via Giuseppe Luigi Lagrange, in Turin, the street where the house of his birth still stands.

• Lagrange, a character from the 2017 rhythm game Arcaea