WordWeb Online

1. Set in a rigidly conventional pattern of behaviour, habits, or beliefs
   "obsolete fossilized ways";
   - fossilised [Brit], ossified

1. Convert to a fossil
   "The little animals fossilized and are now embedded in the limestone";
   - fossilise [Brit]
    
2. Become mentally inflexible
   - fossilise [Brit]

See also: inflexible

Type of: age, convert, get on, maturate, mature, senesce

Encyclopedia: Fossilized