A buffer is like a temporary storage area that helps smooth out differences or delays between two processes. It holds data temporarily, allowing one process to proceed at its own pace while the other process catches up. Full definition
Many private nature reserves function as buffer zones for national parks, allowing for the free movement of species, so the parks do not become «biological islands». (arenalobservatorylodge.com)
Consider including a small percentage of buffer for unexpected school expenses excluded from your list. (financialwellness.org)