NL noun5 •Initialism of Newfoundland and Labrador: a province of Canada. •Initialism of native language. •Abbreviation of Nagaland: a state of India. •(Australia) Initialism of no liability.For example, a no liability company must include in its name the words “No Liability” or its abbreviation “NL” as a warning to persons dealing with such a company. — 2012 •Initialism of night letter.