I saw the word badinage in the book Uncle Tom's Cabin. Do you think that's a typo that really should be bandage?

Badinage is a real word that refers to playful banter between people, a lively exchange that could be considered teasing. Rather than appearing as a misprint, badinage pops up as a valid term in all sorts of literature, including Harriet Beecher Stowe's Uncle Tom's Cabin:

He turned deadly pale when he saw the writing, but still preserved his composure, and finished the playful warfare of badinage which he was at the moment carrying on with a lady opposite . . .

From The Handmaid's Tale, by Margaret Atwood:

Offred's mother maintained a platonic relationship with her mate and engaged in harmless badinage with son-in-law Luke, but was in deadly earnest on the Saturday when her companions burned pornographic magazines in the park.

In Bram Stoker's Dracula:

I couldn't cope in badinage with the worthy Thomas, but I thought I knew a surer way to his heart . . .

Upton Sinclair incorporates the word into his classic, The Jungle:

So, with laughter and shouts and endless badinage and merriment, the guests take their places.

Rather than being a bad spelling error, badinage is a good way to say "funny conversation."