Definitions for "PROTO"
A prefix from the Greek for "before." When used in conjunction with the name of a celestial body, means the state of the body just before it is considered to have formed.
Prefix: first; preliminary; original.
Prefix meaning early.
indicating the first or earliest or original; "`proto' is a combining form in a word like `protolanguage' that refers to the hypothetical ancestor of another language or group of languages"
first protozoan
Keywords:  chief, front, head, title, makes
In general put Proto in front of any title and it makes it "Chief of" or "Head of".