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galacto-

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

    galactopoietic.


galacto- British  

combining form

  1. milk or milky

    galactometer

"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

Usage

What does galacto- mean? Galacto- is a combining form used like a prefix meaning “milk.” It is occasionally used in medical terms, especially in anatomy and pathology.Galacto- comes from Greek gála (stem galakt-), meaning “milk.” The Latin cognate of gála is lac (stem lact-), also meaning “milk,” which is the source of lactose, latte, and perhaps even lettuce. To learn more, check out our Words That Use articles on the combining forms lact-, lacti-, and lacto-.What are variants of galacto-?When combined with words or word elements that begin with a vowel, galacto- becomes galact-, as in galactosis. Want to know more? Read our Words That Use galact- article.

Etymology

Origin of galacto-

< Greek galakto-, combining form of galakt-, stem of gála milk