key worker

noun mainly British

a social worker, mental health worker, or nursery nurse assigned to an individual case, patient, or child

(in Britain) a worker in any of a number of public sector professions considered by the government to be essential to society, for example teachers, police officers, NHS health workers etc

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012