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deci-

American  
  1. a combining form meaning “tenth,” used in words denoting units of the metric system (deciliter ); on this model, extended to other systems (decibel ).


deci- British  

prefix

  1.  d.  denoting one tenth; 10 –1

    decimetre

"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

deci– Scientific  
  1. A prefix that means “one tenth,” as in deciliter, one tenth of a liter.


Usage

What does deci- mean? Deci- is a combining form used like a prefix meaning “tenth.” It is most often used to denote units of the metric system. Deci- comes from the Latin decimus, meaning “tenth.” The word decimate, meaning "to destroy a great number or proportion of" comes from this same Latin root. Find out how at our entry for decimate. A similar word from Greek, déka, meaning “ten,” gives us the combining forms dec-, deca-, and deci-. Want to know more? Check out our Words That Use articles for all three forms. Despite the similarity between the two forms, it’s important not to confuse deci-, which means “tenth,” with deca-, meaning “ten.” A decigram is one-tenth of a gram (0. 1 g), but a decagram is ten grams (10 g).

Etymology

Origin of deci-

< French déci- < Latin decimus tenth

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

This must be how the field operatives whose re- ports she pored over felt when they had to make lightning deci- sions.

From The Verge • Jun. 17, 2018

I wanted to help shape deci- sions that impacted people in positive ways.

From MSNBC • Sep. 9, 2014

For 1-10, 1-100 and 1-1,000 of the units, the prefixes deci-, centi- and milli- are used.

From The Style Book of The Detroit News by News, The Detroit