For migrant workers, Jan Breman has used the term:

Footloose labour

As a livelihood strategy, men migrate out periodically in search of work and better wages, while women and children are often left behind in their villages with elderly grandparents. Migrant workers come mainly from drought-prone and less productive regions, and they go to work for part of the year on farms in the Punjab and Haryana, or on brick kilns in U.P., or construction sites in cities such as New Delhi or Bangalore. These migrant workers have been termed ‘footloose labour’ by Jan Breman.