1. A gradual deterioration or weakening affecting a group, organization, society, or civilization as a whole
The collective decline of manufacturing in the region led to widespread unemployment.
O declínio coletivo da manufatura na região levou ao desemprego generalizado.
2. A shared or mutual decrease in quality, performance, or condition among members of a group
The team experienced a collective decline in motivation after the losses.
O time experimentou um declínio coletivo na motivação após as derrotas.