beruhigen

verb
  1. To calm or soothe someone or something; to make someone or something less agitated or anxious. verb
    She tried to beruhigen the crying baby by singing a lullaby.
    The gentle music helped to beruhigen the nervous audience before the performance.
  2. To reassure someone; to make someone feel less worried or fearful. verb
    He beruhigened his friend by explaining that everything would be fine.
    The doctor beruhigened the patient by explaining the procedure in detail.