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

In a way, she was the proto- character for me.

From Seattle Times • Sep. 21, 2022

But Liszt’s “Two Legends” — exquisitely wrought proto- Impressionist pieces of great finesse — suffered the most.

From Washington Post • Mar. 27, 2016

The Dada classic Four Saints hangs onto the fringe of the repertoire by virtue of its pigeons-on-the-grass-alas text by Stein and Thomson's proto- minimalist, oompah-pah score.

From Time Magazine Archive

Three neuromeres—a proto-, deutero-, and trito-cerebrum—corresponding to those three prosthomeres are sharply marked in the embryo.

From Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 6 "Armour Plates" to "Arundel, Earls of" by Various

You are obviously not familiar with the procedures of Senate panel proto- col.

From Terminal Compromise: computer terrorism: when privacy and freedom are the victims: a novel by Schwartau, Winn