Noun. Mid-18th century.
[from DUO- two, after monologue.]
A conversation between two people;
a dramatic piece with two actors.
Only geeky, nerdy, pedantic types will be interested in the distinction between a duologue and a dialogue (a monologue needs no explanation, surely), but seeing as I'm the geeky, nerdy, pedantic type, I've decided to cover it. Basically, a dialogue is a conversation between "two or more people or groups," whereas a duologue is a conversation between exactly two people. Of course, if you ever forget this and call a duologue a dialogue, only for some nerdy, geeky, pedantic type like me to correct you, you can save yourself by rightly pointing out that it is still a dialogue, as every duologue is by definition also a dialogue (though a dialogue isn't always necessarily a duologue).
Is that clear?
Do please monologue your most logomaniacal comments below.