ostracize or ostracise /osˈtrə-sīz/

1. To exclude from society or from one's social group
2. In ancient Greece, to banish by popular vote, the voters writing on potsherds the name of the person they wanted banished

• keep one's bed
• keep one's breath to cool one's porridge
• keep one's cards close to one's chest
• keep one's chin up
• keep one's cool
• keep one's countenance
• keep one's distance
• keep one's ear to the ground
• keep oneself to oneself
• keep one's end up
• keep one's eye in
• keep one's eye on
• keep one's eyes peeled
• keep one's eyes skinned
• keep one's finger on the pulse
• keep one's fingers crossed
• keep one's hair on
• keep one's hand in
• keep one's head
• keep one's head above water
• keep one's head down
• keep one's mind on
• keep one's mouth shut
• keep one's nose clean
• keep one's options open