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hydr-

1 American  
  1. variant of hydro- before a vowel.

    hydrant.


hydr- 2 American  
  1. variant of hydro- before a vowel.

    hydride.


hydr- British  

combining form

  1. a variant of hydro-

"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 hydr- mean? Hydr- is a combining form used like a prefix that has two distinct senses.The first of these senses is “water,” and this form of hydr- is often used in a variety of scientific and technical terms. Hydr- comes from Greek hýdōr, meaning “water.”The second of these senses is “hydrogen,” and this form of hydr- is occasionally used in a variety of scientific terms, especially in chemistry. Hydrogen, the lightest of the elements, combines with oxygen to form water. The word hydrogen comes from the French hydrogène. The suffix -gen, or its equivalent in French, means "that which produces." Hydrogen literally translates to "that which produces water."What are variants of hydr-?Hydr- is a variant of hydro-, which loses its -o- when combined with words or word elements beginning with vowels. Want to know more? Read our Words That Use article on hydro-.Not every word that begins with the exact letters hydr-, such as hydranth or hydroid, is necessarily using the combining form hydr- to denote “water” or "hydrogen." Learn why hydroid means “hydra-like” at our entry for the word.