Why Is It Called "The Passion" of Jesus Christ?

Why in the world is the brutal torture, suffering, and death of called the "passion?"

There are two answers:

First, it's Latin.  The word passionem means "suffering, enduring," so from that perspective, it makes sense.

Second, it's the reason for the suffering.  Christ absorbs the betrayal, ridicule, beatings, whipping, thorns, dehydration, taunting, denial, heartache, cross, and ultimately death because He loves us.  He loves us with a passion that is unrivaled in all of time.  

So from that perspective, it makes sense as well, no?