A ( 'sign post') is an intended to help the bearer find their way through rough weather. The symbol is attested in the , collected in Iceland by Geir Vigfusson in 1880 (but consisting of material of earlier origin).
Astronomy, physics, chemisty, evolution, artificial intelligence, biology, time travel: it's all covered in this collection of funny science t-shirts.
Related T-shirt Lists: Funny Math T-shirts, Best Dinosaur Tshirts, Amazing Robot Tshirts
Gonna be posting more rejected comics this weekend. There have been plenty from this past week, I just need to pick out some of the less horrible ones. By horrible I mean quality, not in humor crudeness.