Nested
Primary source
Verbatim text below is from the Electronic Code of Federal Regulations (eCFR), a public-domain U.S. government work. Always verify the current version with the eCFR before relying on it for any legal matter.
Full Text
Any tobacco which has been loaded, packed, or arranged to conceal foreign matter or tobacco of inferior grade, quality, or condition. Nested includes any lot of tobacco which contains foreign matter or damaged, injured, tangled, or other inferior tobacco, any of which cannot be readily detected upon inspection because of the way the lot is packed or arranged. (See Rule 17.)
This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.