prot-

¹ American  

1. variant of proto- before a vowel.

   protamine.

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Prot. ² American  

abbreviation

1. Protestant.

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Prot. ¹ British  

abbreviation

1. Protestant

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prot- ² British  

combining form

1. a variant of proto-

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Usage

What does prot- mean? Prot- is a combining form used like a prefix meaning “first,” "foremost,” or “earliest form of.” In terms from chemistry, it specifically denotes either the first in a series of compounds or the compound containing the minimum amount of an element. It is often used in scientific and technical terms, especially in biology. Proto- comes from Greek prôtos, meaning “first.” The word proton, meaning "a positively charged elementary particle," ultimately shares this same Greek root. The Latin cognate of prôtos is prīmus “first,” which is the source of primary and prime. Check out our entries for both words to learn more. What are variants of prot-?Prot- is a variant of proto-, which loses its -o- when combined with words or word elements beginning with vowels. Want to know more? Read our Words That Use proto- article.