constraint vs hang-up

constraint

noun
  • The repression of one's feelings. 

  • An irresistible force or compulsion. 

  • A condition that a solution to an optimization problem must satisfy. 

  • A linkage or other restriction that maintains database integrity. 

  • Something that constrains; a restriction. 

hang-up

noun
  • An emotional difficulty or a psychological inhibition; a complex. 

  • An unforeseen obstacle to progress; a hitch or delay. 

How often have the words constraint and hang-up occurred in a corpus of books? (source: Google Ngram Viewer )