splinter

Noun

• a small thin sharp bit or wood or glass or metal
  • he got a splinter in his finger
    
  • it broke into slivers
    

Verb

• break up into splinters or slivers
  • The wood splintered
    

• divide into slivers or splinters

• withdraw from an organization or communion
  • After the break up of the Soviet Union, many republics broke away
    

Related words

• Synonyms: 
  sliver , secede , break away