Nb is the chemical symbol of niobium.
NB stands for Nominal Bore.
Nickel Back
Niobium
I am not quite sure what you mean by "nb", but I don't think it's a unit of length.
I suspect that NB stands for the Latin phrase nota bene,whick means 'note well'.
nb nb kj:)
NOTA bENE
nicky butler very expensive !!
In grammar, "NB" stands for "nota bene," which is a Latin phrase meaning "note well." It is often used to draw attention to important information or to emphasize a particular point in written text.
Communist, Bolshevik. NB They are not exact equivalents, but close.
destraillar (NB extra 'i') = to unleash, from which destraillo = I unleash