vie. vb, vies, vying or vied. 1. (intr; foll by with or for) to contend for superiority or victory (with) or strive in competition (for). 2. (tr) to offer, exchange, or display in rivalry. [C15: probably from Old French envier to challenge, from Latin invÄ«tÄre to invite].
On rare occasions, a halfback is asked to throw the ball when running a HB option. This play is generally referred to as a half-back pass, regardless if the player throwing the football is a tailback or fullback.
HL stands for  H ypotenuse, L eg (t he longest side of a right-angled triangle is called the hypotenuse , the other two sides are called legs). It means we have two right-angled triangles with.