atavism /atˈə-vi-zm/

1. The reappearance of ancestral, but not parental, characteristics
2. Reversion to an ancestral, or to a primitive, type

atavistˈic adjective

• horsecar
• horsecars
• horse chestnut
• horse chestnuts
• horse-cloth
• horse-cloths
• horse-collar
• horse-collars
• horse-coper
• horse-copers
• horse-couper
• horse-coupers
• horse-courser
• horse-coursers
• horsed
• horse-dealer
• horse-dealers
• horse-dealing
• horse-doctor
• horse-doctors
• mammographies
• mammographs
• mammography
• mammon
• mammonish