'last word' definitions:

Definition of 'last word'

(from WordNet)
noun
The final statement in a verbal argument; "she always gets the last word"
noun
An authoritative statement; "my doctor has the last word on the medicines I take"
noun
Elegance by virtue of being fashionable [syn: chic, chicness, chichi, modishness, smartness, stylishness, swank, last word]

Synonyms of 'last word'

From: Moby Thesaurus