banker

Etymology 1

bank + -er, after French banquier.

noun

1. One who conducts the business of banking; one who, individually, or as a member of a company, keeps an establishment for the deposit or loan of money, or for traffic in money, bills of exchange, etc.
   185?, Charles Dickens, Little Dorrit I have a good banker in this city, but I would not wish to draw upon the house until the time when I shall draw for a round sum.
2. The dealer in a casino, or one who keeps the bank in a banking game.
3. (obsolete) A money changer.
4. The stone bench on which a mason cuts or squares his work.

Etymology 2

From bank (“an elevation, or rising ground”) + -er (relational noun suffix) or + -er (occupational suffix).

noun

1. A vessel employed in the cod fishery on the banks of Newfoundland.
   May 20 1815, John Quincy Adams, letter to a merchant I think the 584 Bankers may be put down 36,540 tons, navigated by 4,627 men and boys
2. (UK, dialect) A ditcher; a drain digger.
   But this was no storm, the bankers could have told him. It was break of the year. 1941, Ernestine Hill, My Love Must Wait, A&R Classics, published 2013, page 6
3. (mining) A banksman.

Etymology 3

From bank (“an incline or hill”) + -er.

noun

1. (rail transport, Britain, Australia) A railway locomotive that can be attached to the rear of a train to assist it in climbing an incline.
   Between them these engines work passenger trains on the Keith line, and also act as bankers up to Dava when required. 1944 January and February, W. McGowan Gradon, “Forres as a Railway Centre”, in Railway Magazine, page 23
   Because of a shortage of W.R. pannier tanks, two "E6" 0-6-2 tanks, Nos. 32410/5, were engaged as bankers on the Folkestone Harbour branch at the beginning of March; …. 1960 May, “Motive Power Miscellany: Southern Region”, in Trains Illustrated, page 314