The phrase "cumulative effect" means that something gradually adds up or builds up over time, resulting in a greater impact or outcome than just the individual parts. Full definition
He said the current recession was as a result of cumulative effects of worldwide economic downturn and failure in the past to plan and save for difficult times. (nigeriapoliticsonline.com)
In addition, the evidence for cumulative effects suggests several possible points of intervention with anxious children and their parents. (cambridge.org)
For instance, our short - lived acts can have cumulative effects upon our atmosphere — each breath we take changes its composition a little. (religion-online.org)