economy class syndrome

Từ điển Oxford Advanced Learner 8th

eˈconomy class syndrome 7 [economy class syndrome] BrE NAmE noun uncountable (BrE)
the fact of a person suffering from ↑deep vein thrombosis after they have travelled on a plane. This condition is thought to be more common among people who travel in the cheapest seats because they do not have space to move their legs much.