What does "quadruple" mean?

Quadruple: Fourfold; as, to make quadruple restitution; a quadruple alliance. Quadruple time (Mus.), that in which each measure is divided into four equal parts.

Additional senses

  1. 2.four times the sum or number; a fourfold amount; as, to receive to quadruple of the amount in damages.
  2. 3.To multiply by four; to increase fourfold; to double; to double twice. A. Smith.
  3. 4.To be multiplied by four; to increase fourfold; to become four times as much.

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