Green’s Dictionary of Slang

retsam n.

[backsl.]

a master, a manager.

[UK](con. late 19C) Northern Whig 12 Sept. 8/6: ‘Kacab-Kalat’ is really ‘back-talk’. One shop-boy would ask another, ‘Where’s the retsam?’ and the reply [...] ‘Texan Road,’ or ‘Enog to rennid.’ This interchange simply meant ‘Where’s the master?’ with the answer ‘Next door’ or ‘Gone to dinner’.