a combining form meaning “swift,” used in the formation of compound words: tachygraphy.
Origin of tachy-
< Greek, combining form of tachýs
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
swift or acceleratedtachycardia; tachygraphy; tachylyte; tachyon; tachyphylaxis
Word Origin for tachy-
from Greek takhus swift
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
word-forming element meaning "rapid, swift, fast," from Latinized comb. form of Greek takhy "swift."
Online Etymology Dictionary, © 2010 Douglas Harper
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.