1. (biology) a hypothesis of directed evolution (as opposed to natural selection of random variations)

Encyclopedia: Orthogenesis

• digressive
• digs
• dihedral
• dihybrid
• dihybrid cross
• dihydric alcohol
• dihydrostreptomycin
• dihydroxyphenylalanine
• Dijon
• dik-dik
• dika
• dika bread
• dika nut
• dike
• diktat
• Dilantin
• dilapidate
• dilapidated
• dilapidation
• dilatable
• dilatation
• dilatation and curettage
• dilate
• dilater
• dilation