conjunction
- least action, principle of
- least common denominator
- least common multiple
- least squares
- least squares theorem
- least upper bound
- least value
- leaving variable
- Lebesgue, Henri
- Lebesgue integration
- left and right derivative
- left inverse
- left‐handed system
- Legendre, Adrien‐Marie
- Legendre polynomials
- Legendre's conjecture
- Legendre's differential equation
- Legendre symbol
- Leibniz, Gottfried Wilhelm
- Leibniz's integral rule
- Leibniz's Theorem
- lemma
- length
- length
- length of an arc