يعرف به أحوال اللفظ العربي
Through it, one recognizes the states or properties of Arabic expression.
The definition is concerned specifically with those properties through which speech conforms to the occasion. It is not another name for all lexical, morphological and grammatical facts; rather, it studies choices in expression that affect rhetorical suitability.
These include adding or omitting emphasis, changing the order of constituents, abbreviating and expanding a statement where there is a reason to do so.