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1. Compel to behave in a certain way
   "duty constrains one to act often contrary to one's desires or inclinations";
   - enforce, impose
    
2. To close within bounds, or otherwise limit or deprive of free movement
   - restrain, confine, hold
    
3. (of laws or regulations) make more restrictive, or impose greater penalties
   - stiffen, tighten, tighten up

Derived forms: constrained, constrains, constraining

Type of: bound, compel, confine, disable, disenable, incapacitate, limit, obligate, oblige, restrict, throttle, trammel

Encyclopedia: Constrain