Definition of Not negotiable:
Words marked or written on a bill of exchange (such as a draft) which stop the bill from being a negotiable instrument. While a check may be made non-negotiable merely by crossing it (drawing two parallel lines across its face), all other bills must have the words Not Negotiable written on their face. Any transferee (the current holder) of such a bill cannot have better right of ownership of the bill than the transferor (the previous holder). See also crossed check.
Meaning of Not negotiable & Not negotiable Definition