Like most professions, Surveyors, Engineers, & Geodesists have their own language and abbreviations for things. Below are many of the abbreviations which may be encountered when using or hunting benchmarks.

AZM: Azimuth

BOR: Bureau Of Reclamation

Caltrans:  California Department of Transportation (Also see CDH, CDOT)
CDH: California Department of Highways (Also see CDOT, Caltrans)
CDOT:  California Department of Transportation (Also see CDH, Caltrans)
CPost: California Post

DOI: United States Department of the Interior
DOT: Department of Transportation
DWR: Department of Water Resources

FCBCM: Fresno County Brass Cap Monument

GE:  Geodetic Engineer
GLO: Government Land Office

NGS: National Geodetic Survey

PE: Professional Engineer
PLS: Professional Land Surveyor
PLSS:  Public Land Survey System

RCE:  Registered Civil Engineer (Note: in the State of California, a Civil Engineer licensed prior to 1982 can practice Land Surveying.)
RE: Registered Engineer (Also see PE)
RM:  Reference Monument

SSTTRR:  Section Township Range - the breakdown system of the Public Land Survey System

TBM: Temporary Benchmark
TTRRSS:  Township Range Section - the breakdown system of the Public Land Survey System

USC&GS:  United States Coast & Geodetic Survey
USBPR: United States Bureau of Public Roads (Also see CDH)
USGS: United States Geological Survey