tachy-

American  

1. a combining form meaning “swift,” used in the formation of compound words.

   tachygraphy.

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tachy- British  

combining form

1. swift or accelerated

   tachycardia

   tachygraphy

   tachylyte

   tachyon

   tachyphylaxis

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Usage

What does tachy- mean? Tachy- is a combining form used like a prefix meaning “swift.” It is often used in scientific and medical terms. Tachy- comes from the Greek tachýs, meaning “swift.”What are variants of tachy-?A variant of tachy- is tacheo-, as in tacheometer. Closely related to tachy- is the combining form tacho-, which you can learn more about in our Words That Use tacho- article.

Etymology

Origin of tachy-

< Greek, combining form of tachýs