Other forms: colloquia; colloquiums
A colloquium is an academic conference or meeting. At a colloquium, you’ll spend a couple of days listening to lectures with a group of people who all know a lot about one particular subject.
The root of colloquium is the Latin loqui, meaning “to talk, ” which is what people tend to do at a conference. If you’re attending a colloquium on hummingbirds, you’re going to meet a lot of biologists who talk about hummingbirds. If you’re giving a lecture at the same colloquium, you’d better hope you know a lot about hummingbirds or you might get run out of the conference!