Orthology

Orthology (Greek orthos 'straight, upright' and logos 'word, customer') means

• in medicine, the knowledge or science of the normal state of an organ or system; the opposite is the pathology
• in genetics the relationship between two genes in different species that have a common ancestry, see homology (genetics) #homology between duplicated or foreign genes

This is a disambiguation page for differentiating between several terms identified with the same word.