Learn Swedish: Tidtabellen är otydlig, men tåget avgår klockan åtta prick. - The timetable is unclear, but the train departs at eight o'clock sharp.

In English, you say a train departs "at" a certain time. In Swedish, when using klockan (the clock) to specify a time, you don't use a preposition. You just say avgår klockan åtta (literally "departs the clock eight").

What does prick literally mean here?

Literally, prick means "dot" or "spot". When talking about time, it is the exact equivalent of saying "on the dot" or "sharp" in English. So klockan åtta prick means "eight o'clock sharp".

Why is the verb avgår used instead of just går?

Both are actually fine! Tåget går is very common for saying "the train leaves". Avgår is a slightly more formal word specifically meaning "departs", which is exactly what you would expect when talking about a tidtabell (timetable).

How does the word otydlig (unclear) get its meaning?

It uses the prefix o-, which is the Swedish equivalent of the English "un-" (meaning "not"). Tydlig means "clear", so adding the prefix makes it otydlig ("unclear").