Words that change meaning with a different article?

Oh I love this topic! I've been collecting these. Here's my list: der See (lake) vs die See (sea) der Band (book volume) vs das Band (ribbon/tape) vs die Band (music band) der Leiter (leader/manager) vs die Leiter (ladder) der Kiefer (jaw) vs die Kiefer (pine tree) das Steuer (steering wheel) vs die Steuer (tax) der Verdienst (earnings/income) vs das Verdienst (merit/achievement) der Schild (shield) vs das Schild (sign/placard) der Tau (dew) vs das Tau (thick rope) der Bauer (farmer) vs das Bauer (birdcage) - this one surprised me! der Flur (hallway) vs die Flur (open fields/meadow) And yes, these come up! I once told my host family I was going to "die See" when I meant the lake near our house. They thought I was driving to the North Sea for a swim lol. My host dad was very confused for about 10 seconds before he figured it out.

Good list from Emma. I'd add der Erbe (heir) vs das Erbe (inheritance) and der Gehalt (content/substance) vs das Gehalt (salary). To answer your question about how common they are: der See vs die See and das Steuer vs die Steuer come up all the time. The others are less frequent in daily conversation but still worth knowing. Would a German be confused? Probably not for long. Context usually makes it clear. If you're standing next to a lake and say "die See ist schön", they'll know you mean the lake even though you used the wrong article. But in writing or formal situations, it could cause a real misunderstanding.