proto-
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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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What does "dignity" mean?
Also especially before a vowel, prot-.
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022
How to use proto- in a sentence
British Dictionary definitions for proto-
proto-
sometimes before a vowel prot-
combining form
indicating the first in time, order, or rankprotomartyr
primitive, ancestral, or originalprototype
indicating the reconstructed earliest stage of a languageProto-Germanic
indicating the first in a series of chemical compoundsprotoxide
indicating the parent of a chemical compound or an elementprotactinium
Word Origin for proto-
from Greek prōtos first, from pro before; see pro- ²
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
Medical definitions for proto-
proto-
pref.
First in time:prototype.
First formed; primitive; original:protoplast.
Having the least amount of a specified element or radical:protoporphyrin.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.