/ ˈkjuːmjələtɪv; NAmE -leɪtɪv/ adjective
1.
having a result that increases in strength or importance each time more of sth is added :
the cumulative effect of human activity on the world environment
2.
including all the amounts that have been added previously :
the monthly sales figures and the cumulative total for the past six months
► cu·mu·la·tive·ly adverb