[Fiji Hill]

I was taught it meant "hosteler," as in "innkeeper." "Zimmer" is German for "room," so a Zimmer-mann would be a "room-man," or one who keeps rooms for let.

A Zimmermann makes rooms. If he's a master at this trade, he's a Zimmermeister (master carpenter).

[IronJack]

The online German translator agrees with you. My German teacher must have been an idiot. Or I was paying too much attention to the frauleins ...