From Longman Dictionary of Contemporary Englishumbrella organization/group/agency etcumbrella organization/group/agency etcan organization that includes many smaller groups → umbrella
Examples from the Corpus
umbrella organization/group/agency etc• La Raza is an umbrella group of almost 200 Hispanic advocacy groups.• Inpeg, the Czech environmentalist umbrella group that organised the protests, refused to condemn Molotov cocktails being thrown at police.• About 130 professional and human-rights groups are folded into Concilio Cubano, a rickety umbrella group set up last year.• The umbrella group we'd formed in 1987 had fallen into abeyance, but the name still meant something. 