nb Meaning, Definition & Usage

1. noun a soft grey ductile metallic element used in alloys; occurs in niobite; formerly called columbium
   niobium; atomic number 41.
   
2. noun a Latin phrase (or its abbreviation) used to indicate that special attention should be paid to something
   N.B.; nota bene.
   
   • the margins of his book were generously supplied with pencilled NBs

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