fixation in WordNet English dictionary

1. an abnormal state in which development has stopped prematurely
   arrested development  fixation  infantile fixation  regression 
   
2. (histology) the preservation and hardening of a tissue sample to retain as nearly as possible the same relations they had in the living body
   fixation  fixing 
   
3. the activity of fastening something firmly in position
   fixation 
   
4. an unhealthy and compulsive preoccupation with something or someone
   obsession  fixation