Kenneth G. Wilson (1923–). The Columbia Guide to Standard American English. 1993.
not about to
as in She’s not about to resign, can mean simply “does not intend to” but in recent years has become a Standard idiom meaning “is determined not to.” The locution is thought to be Southern or South Midland in origin, and it is still usually encountered at Conversational levels and in the writing that imitates them, although today’s Edited English sometimes has it too.
