quad·ru·ple (kwŏ-drpəl, -drŭpəl, kwŏdr-pəl)
1. Consisting of four parts or members.
2. Four times as much in size, strength, number, or amount.
3. Music Having four beats to the measure.
A fourfold amount or number.
tr. & intr.v. quad·ru·pled, quad·ru·pling, quad·ru·ples
To multiply or be multiplied by four: quadrupled the order; quadrupled in size.
[From Middle English quadriple, fourfold amount, and quadruple, tooth with four roots, both from Old French quadruple, from Latin quadruplum, from neuter of quadruplus, fourfold : quadru-, quadri-, quadri- + -plus, -fold; see pel-2 in the Appendix of Indo-European roots.]
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