- Protobiology Subst. Adj.
- Protobiont Subst. Adj.
- Protobitumen Subst. Adj.
- Protoblast Subst.
- Protocatechate Subst. Adj.
- Protochloride Subst. Adj.
- Protococcus Subst. Eigenn.
- Protocol Subst. Adj. Verb
- Protocontinent Subst. Adj.
- Protoderm Subst. Adj.
- Protofascist Adj. Subst.
- Protofibril Subst. Adj.
- Protogalaxy Subst. Adj.
- Protogyny Subst.
- Protohematin Subst. Adj.
- Protoheme Subst. Adj.
- Protohippus Subst. Eigenn.
- Protohistorian Subst.
- Protohistory Subst.
- Protohuman Adj. Subst.
- Protolanguage Subst. Adj.
- Protolysate Subst. Adj.
- Protolysis Subst. Adj.
- Proton Subst. Adj.
- Protonation Subst. Adj.
- Protonema Subst. Adj.
- Protonophore Subst. Adj.
- Protooncogene Subst. Adj.
- Protopectin Subst. Adj.
- Protopectinase Subst. Adj.
- Protophloem Subst. Adj.
- Protophyte Subst.
- Protoplanet Subst. Adj.
- Protoplasm Subst. Adj.
- Protoplasmolysis Subst.
- Protoplast Subst.
- Protoplastic Adj. Subst.
- Protopodite Subst. Adj.
- Protopope Subst.
- Protoporphyria Subst.
- Protoporphyrin Subst. Adj.
- Protopresbyter Subst.
- Protostar Subst.
- Protostele Subst. Adj.
- Prototherian Adj. Subst.
- Protothetics Subst.
- Prototoxin Subst. Adj.
- Prototroph Subst.
- Prototropy Subst.
- Prototype Subst. Verb Adj.
- Prototyping Subst. Adj.
- Protoxide Subst. Adj.
- Protoxylem Subst. Adj.
- Protozoa Subst.
- Protozoacide Subst. Adj.
- Protozoan Subst. Adj.
- Protozoologist Subst.
- Protozoology Subst.
- Protozoon Subst.
- Protract Verb Subst.