proto-

American  

1. a combining form meaning “first,” “foremost,” “earliest form of,” used in the formation of compound words (protomartyr; protolithic; protoplasm ), specialized in chemical terminology to denote the first of a series of compounds, or the one containing the minimum amount of an element.

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proto- British  

combining form

1. indicating the first in time, order, or rank

   protomartyr

2. primitive, ancestral, or original

   prototype

3. indicating the reconstructed earliest stage of a language

   Proto-Germanic

4. indicating the first in a series of chemical compounds

   protoxide

5. indicating the parent of a chemical compound or an element

   protactinium

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Usage

What does proto- mean? Proto- is a combining form used like a prefix meaning “first,” "foremost,” or “earliest form of.” In terms from chemistry, it specifically denotes 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 proto-?When combined with words or word elements that begin with a vowel, proto- becomes prot-, as in protium. Want to know more? Read our Words That Use prot- article.

Etymology

Origin of proto-

< Greek, combining form representing prôtos first, superlative formed from pró; pro- ²

Example Sentences

All of this comes on the heels of 2020, which Proto described as “an absolutely extraordinary year” in terms of the extra work and stress placed on local election offices.

From Los Angeles Times

Sonoma County elections chief Deva Marie Proto said she worries about staff burnout and the general toll on resources.

From Los Angeles Times

“Horror at Glyka Nera,” wrote the website Proto Thema.

From Reuters

"Has Trump started ranting about Time magazine yet? If not, either he's not watching tv - the only place he gets his news - or he's asleep," one Twitter user said, adding, "Or calling his corrupt Proto fascists in the GOP with more thoughts on their war on democracy."

From Salon

In fact, the envelopes were empty and from the 2018 election, Ms. Proto said.

From New York Times