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actino-

American  
  1. a combining form with the meaning “ray, beam,” used in the formation of compound words, with the particular senses “radiation” in the physical sciences (actinometer ) and “having raylike structures,” “radiate in form” in biology (actinomyces; actinopod ).


actino- British  

combining form

  1. indicating a radial structure

    actinomorphic

  2. indicating radioactivity or radiation

    actinometer

"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

Etymology

Origin of actino-

< Greek, combining form representing aktī́s (genitive aktînos ) ray, beam; -o-

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.

You can follow the actino with Rob Smyth ...

From The Guardian

"There are two classes of organism in water - the cyano bacteria, which is commonly known as blue/ green algae, and actino mycetes, which are responsible for the damp or earth smell."

From BBC