coprocessor

noun
  1. computing a microprocessor circuit that operates alongside and supplements the capabilities of the main processor, providing, for example, high-speed arithmetic
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coprocessor in Science

coprocessor

[kōprŏs′ĕs-ər]
  1. A microprocessor distinct from the central processing unit. A coprocessor performs specialized functions that the central processing unit cannot perform or cannot perform as well and as quickly.
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