Peer review is defined as the process by which articles submitted for publication in a scholarly journal are reviewed by experts in the subject field (peers) for evaluation and comment (review). Peer-reviewed journals contain articles that have undergone the rigorous peer review process. Another term for peer-reviewed is "refereed."
PLOS Biology is an open-access, peer-reviewed general biology journal published by PLOS, a nonprofit organization of scientists and physicians committed to making the world's scientific and medical literature a public resource. New articles are published online weekly; issues are published monthly.