proto- or prot-
1. First in time; earliest: protolithic.
2. First formed; primitive; original: protohuman.
3. Proto- Being a form of a language that is the ancestor of a language or group of related languages: Proto-Germanic.
4. Having the least amount of a specified element or radical: protoporphyrin.
[Greek prōto-, from prōtos; see per1 in the Appendix of Indo-European roots.]
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