externshipex‧tern‧ship /ˈekstɜːnʃɪp $ -tɜːrn-/ noun [countable] American English 
a job that a university student does in order to gain experience in a particular area of work. Externships are usually not paid and usually last only a short time: 
an externship in a law firm
a job that a university student does in order to gain experience in a particular area of work. Externships are usually not paid and usually last only a short time: an externship in a law firm