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costo-

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

    costoclavicular.


Usage

What does costo- mean? Costo- is a combining form used like a prefix meaning “rib.” It is often used in medical terms, especially in anatomy and pathology. Costo- comes from the Latin costa, meaning “rib, side.” The word costa was borrowed directly into English as a term for a “rib,” among other senses. The Latin costa is also the source of the word coast. Explore more at our entry for coast. What are variants of costo-?When combined with words or word elements that begin with a vowel, costo- becomes cost-, as in costalgia.

Etymology

Origin of costo-

< Latin cost ( a ) rib ( see costa) + -o-