Amazon PPC glossary
Bulk file
A spreadsheet-based export and import format used to view and edit large numbers of campaigns, ad groups, and keywords at once, outside the advertising console.
Where it matters most: Book 5, The Advanced PPC Clarity Guide, in the chapter “Bulk File Workflows.”
Go deeper
The glossary gives you the one-line answer. The Advanced PPC Clarity Guide explains why it matters and what to do about it.