Prefix
A combining form prefix signifying first, primary, primordial; as, protomartyr, the first martyr; protomorphic, primitive in form; protoplast, a primordial organism; prototype, protozoan.
Denoting the first or lowest of a series, or the one having the smallest amount of the element to the name of which it is prefixed; as protoxide, protochloride, etc.
Sometimes used as equivalent to mono-, as indicating that the compound has but one atom of the element to the name of which it is prefixed. Also used adjectively.
Source: Webster's dictionaryIn 2001, archaeologists studying the remains of two men from Mehrgarh made the discovery that the people of the Indus Valley Civilization had knowledge of proto- dentistry from the early Harappan periods. Source: Internet
In Detroit a proto- techno music sound began to emerge with the recordings of Juan Atkins, Derrick May and Kevin Saunderson. Source: Internet