The Volokh Conspiracy
Mostly law professors | Sometimes contrarian | Often libertarian | Always independent
Just ran across this abbreviation for the first time in a court case; it's used in New York court citations, when the name of the county is included, and it means Bronx County, e.g., "See People v. Brown, 2022 NYLJ LEXIS 1051 (Sup Ct Bx Co.)." There are many references to it, and (less commonly) "Bx. Cty.," "Bx. Cnty.," and "Bx. County," so it's not just a one-off, though it's still much less common than the fully spelled out Bronx. A quick search reveals that Bx for Bronx is a common non-legalese reference, though seemingly pretty slangy; not all such abbreviations make their way into legal usage.