homesickness       
noun [ U ] uk/ˈhəʊm.sɪk.nəs/ us/ˈhoʊm.sɪk.nəs/
 思乡,想家
the feeling of being unhappy because of being away from home for a long period
  I was almost overcome with homesickness. 思乡之情快让我受不了了。 
 She saw a counsellor to discuss her homesickness. 她去见了一位心理咨询师,讨论她想家的情绪。 
 See: homesick
 - More examples
 - Many of the emigrants are now returning, drawn by opportunity, not homesickness.
 - Most of the time a student’s homesickness passes in few days.
 - He admits to bouts of homesickness.