Bí·o-Bí·o 
(bē′ō-bēō)
(bē′ō-bēō) A river of central Chile flowing about 385 km (240 mi) generally northwest from the Andes to the Pacific Ocean near Concepción.
- protolithic
- protomartyr
- protomorph
- protomorphic
- proton
- protonema
- protonemal
- protonematal
- protonic
- protonotary
- protonotary
- protonotary apostolic
- proton-proton chain
- proton pump inhibitor
- proton synchrotron
- proto-oncogene
- protopathic
- protopathy
- protoplanet
- protoplanetary disk
- protoplasm
- protoplasmal
- protoplasmatic
- protoplasmic
- protoplast