constraint vs suppression

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. 

suppression

noun
  • A process in which a person consciously excludes anxiety-producing thoughts, feelings, or memories. 

  • The act or instance of suppressing. 

  • The state of being suppressed. 

  • The entirety of acts aimed at stopping or preventing the enemy to execute such unwanted activities like firing, regrouping, observation or others. 

  • A subconscious adaptation by a person's brain to eliminate the symptoms of disorders of binocular vision such as strabismus, convergence insufficiency and aniseikonia. 

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