consortium(数家公司或银行联合组成的)财团, 联营企业
a group of companies or organizations who are working together to do something:
a consortium of oil companies
The aircraft will be built by a European consortium

Group：集团 several companies that all have the same owner [↪ chain]:
a giant textiles group

区别：Group是数家公司，同一老板的集团公司；consortium则是数家公司为承接某一项目，联合起来，股东有数家的集团公司