Also called: Ends
In knitting, the word “tail” can refer to two things.
1) A tail is any end of yarn sticking out after you finish a project. Tails must be woven in to prevent unraveling. Whenever cutting a piece of yarn, always leave at least a 6-in. (15 cm) tail so that you can weave it in later. This type of tail is also called an “end.”
2) In doing any kind of long-tail cast-on, the tail is the strand of yarn coming from your needle that is not the working yarn.