# constraint

Pronunciation: say "kuhn-STRAYNT" US/UK /kənˈstɹeɪnt/, AUS /kənˈstɹæɪnt/

## Noun

1. A restriction or limitation that holds something within certain bounds.
   - Simple: A rule or limit that stops you from doing what you want.
   - _Budget constraints forced the team to cut several features._
   - _The new policy placed a constraint on how much water each household could use._
2. An irresistible force or compulsion that drives a person to act.
   - Simple: A strong force or pressure that makes you do something and that you cannot resist.
   - _A strange constraint drove him to confess everything that night._
   - _She acted under a constraint she could neither name nor resist._
3. The act of holding back or hiding one's true feelings.
   - Simple: Holding back your true feelings instead of showing them.
   - _He answered with obvious constraint, keeping his real opinion hidden._
   - _The constraint in her voice told everyone she was upset._
4. In optimization, a condition that any acceptable solution to a problem must meet.
   - Simple: A rule that any correct answer to a problem must follow.
   - _The optimization model included a constraint limiting total cost to the available budget._
   - _Adding a single constraint can shrink the set of feasible solutions dramatically._
5. A linkage or other restriction that maintains the integrity of data stored in a database.
   - Simple: A rule that keeps the information in a database correct and in order.
   - _A foreign key constraint links each order to a valid customer record._
   - _The developer added a constraint to prevent duplicate entries in the table._

## Origin

The word comes from Middle English constreynt, from Old French constreinte, the past participle of constreindre ("to constrain"), which came from Latin cōnstringō (linked to the past participle cōnstrictus).

Source: DictionaryAI, https://dictionaryai.com/define/constraint (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).