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.
98,828 entries. Headwords are matched first, then definition text.