obligate

Adjective

• restricted to a particular condition of life
  • an obligate anaerobe can survive only in the absence of oxygen
    

Verb

• bind by an obligation; cause to be indebted
  • He's held by a contract
    
  • I'll hold you by your promise
    

• commit in order to fulfill an obligation
  • obligate money
    

• force somebody to do something
  • We compel all students to fill out this form
    

Related words

• Synonyms: 
  oblige , bind , hold , compel