'Yields the part-of-speech tag (NOUN, VERB, ADJECTIVE or ADVERB).'

@property
def pos(self):

    pos = self._synset.pos
    if (pos == 'noun'):
        return NOUN
    if (pos == 'verb'):
        return VERB
    if (pos == 'adjective'):
        return ADJECTIVE
    if (pos == 'adverb'):
        return ADVERB
