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oct-

1 American  
  1. variant of octa- or octo- before a vowel.

    octal.


oct. 2 American  

abbreviation

  1. octavo.


Oct. 3 American  

abbreviation

  1. October.


Oct 1 British  

abbreviation

  1. October

"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

oct- 2 British  

combining form

  1. (used before a vowel) a variant of octo-

"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 oct- mean? Oct- is a combining form used like a prefix meaning “eight.” It is used in a great many scientific and technical terms. Octo- comes from the Greek oktṓ, meaning “eight.” The Latin equivalent, which is almost identical in spelling and pronunciation, is octō. What are variants of oct-?Oct- is a variant of octa- or octo-, which loses its -a- or -o- when combined with words or word elements beginning with vowels. Want to know more? Check out our Words That Use entries for both octa- and octo-.

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.

OCT scanners -- used in most high street opticians -- use light waves to create a cross-sectional picture of the retina, displaying each individual layer, within a few minutes.

From Science Daily • Dec. 5, 2023

"OCT scans are more scalable, non-invasive, lower cost and quicker than brain scans for this purpose," she added.

From BBC • Aug. 22, 2023

OCT 24: At a public event attended by Chinese regulators, Ma says the financial and regulatory system stifled innovation and must be reformed to fuel growth.

From Reuters • Jun. 9, 2022

Thouvenin used his upgraded OCT technique to track the movement and metabolism of subcellular organelles and other structures inside living retina tissue from mice and monkeys.

From Nature • Sep. 18, 2018

I knew from the training film that I’d just been fitted with an OCT.

From "Ready Player One: A Novel" by Ernest Cline

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