1. Coming next after the seventh and just before the ninth in position
   - 8th

1. Position eight in a countable series of things
   "She was the eighth person to arrive at the party"
    
2. One part in eight equal parts
   "The recipe called for one-eighth of a cup of sugar";
   - one-eighth

Derived forms: eighths

See also: ordinal

Type of: common fraction, rank, simple fraction, vulgar fraction [Brit]

Encyclopedia: Eighth