From Longman Dictionary of Contemporary Englishblacklegblack‧leg /ˈblækleɡ/ noun [countable] British English BELsomeone who continues to work when other workers are on strike – used to show disapproval
Examples from the Corpus
blackleg• Picketing gave way to marches through factories, when workers would chase blacklegs and occasionally kidnap managers.• Across the road in a secure compound are the buildings that house the mostly out-of-state blacklegs.• The blackleg buses disappeared off the streets and other vehicles which had been beginning to return to the roads.From Longman Business Dictionaryblacklegblack‧leg /ˈblækleg/ noun [countable] British English a worker who continues to work during a strike or who does the work of someone who is on strikeChinese seamen were brought in from outside and used as blacklegs by the employers. → see also strikebreaker 