[1] : The Collaborative International Dictionary of English v.0.48

cambist \cam"bist\, n. f. cambiste, it. cambista, fr. l.
   cambire to exchange. see change.
   a banker; a money changer or broker; one who deals in bills
   of exchange, or who is skilled in the science of exchange.
   1913 webster
see also:
change 

[2] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

cambist. a person skilled in exchange; one who deals or trades in promissory 
notes or bills of exchange. 

Cambist >> C Words
Cambist, definition of term: Cambist
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