What is meant by Jersey t-shirts?

[szjacobson]

In ItsDeductible, what is defined as "Jerseys" under Men's clothing?  I understand it is a match if you have football jerseys, but what about the Underarmour or other dry fit t-shirts?  Are they considered t-shirts or jerseys?

[tygrtchr]

"Jersey" is a type of fabric--usually referred to as "slinky" or "dressy."  An UnderArmor t-shirt would be considered a "jersey shirt."