Definition of "all but"
all but
adverb
not comparable
Very nearly; everything short of. Most often precedes a verb or adjective.
Quotations
When the first wave of postwar immigrants arrived in Britain in the 1950s and ’60s, it was a period of rising wages, full employment, an expanding welfare state and strong trade unions. Today, Britain’s manufacturing base has all but disappeared, working-class communities have disintegrated, unions have been neutered and the welfare state has begun to crumble.
2013 September 28, Kenan Malik, “London Is Special, but Not That Special”, in New York Times, retrieved 28 September 2013