The extent to which something is dispensable(noun)
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Use "dispensability" in a sentence
"Just a straw in the wind, but the Corzine remark mirrors a callousness, a coarse attitude about the "dispensability" of the aged, that one sees in the debate over health-care reform."
"This dispensability is, in fact, the key political problem of free trade."
"This ideological turning point was first made explicit around 1981, when Ronald Reagan's mass firing of striking air traffic controllers was taken as signifying federal approval of a new and more adversarial era in labor management relations, made feasible largely by the increasing dispensability of American workers."