let loose

Verb

• turn loose or free from restraint
  • let loose mines
    
  • Loose terrible plagues upon humanity
    

• express audibly; utter sounds (not necessarily words)
  • She let out a big heavy sigh
    
  • He uttered strange sounds that nobody could understand
    

Related words

• Synonyms: 
  unleash , loose , utter , emit , let out