Abstract：Abstract: The unit of meaning has been an issue of central importance in corpus linguistics. This paper discusses Sinclair's reformulation of the concept of the unit of meaning, i.e. meaning-shift unit (MSU). It focuses on MSU's implications and the analytical procedure. As the study shows, the normal primary carrier of meaning extends beyond the single word and presents itself in an MSU. Co-selection patterns play an important role in meaning shift, while semantic prosody is the decisive factor underlying the change in the unit of meaning. The analysis of an MSU involves the identification of its canonical form along with its variants, and there are four steps in this procedure. Based on the phraseological variations in each MSU, a new local grammar approach for structuralizing co-selection patterns is also explored in this paper. Lastly, this paper addresses MSU's rich implications for and insights into the future of corpus linguistics.
Key words：meaning-shift unit; co-selection pattern; canonical form; local grammar
