noun: Initialism of personal navigation assistant.
noun: (biochemistry) Initialism of peptide nucleic acid. [(biochemistry) A synthetic organic polymer similar to DNA or RNA; the sugar backbone of nucleic acids is replaced by N-(2-aminoethyl)-glycine linked through peptide bonds - considered a possible precursor to RNA]
noun: (pathology) Initialism of pulmonary nodular amyloidosis.
noun: Initialism of Polish National Alliance.
noun: (in the Philippines) Initialism of Philippine News Agency.