Because there is no such religion as "protestant." That word is a descriptive used by historians to identify a number of movements that objected to catholic excesses and erroneous theology during the middle ages.
There are Anglicans, Presbyterians, Baptists, etc., etc. They are as different from each other as they are from catholicism. In fact, catholicism is simply another denomination in terms of today's world.
These definitions are all either offered by calvinists on this thread or are condensations of definitions on this site recommended by JerryM: Calvinist Tulip Definition Site recommended by Jerry
T - - Total Depravity means that Natural Man is totally sinful and does not ever WANT in his own spirit to know Christ.
U - - Unconditional Election means that God has elected for His own glory, in accordance with His own will and without regard for the merit of those elected, some for salvation and some to be left in their sins.
L - - Limited Atonement means that Christ died specifically and only for the sins of those who would ever truly believe in Him.
I - - Irresistible Grace means that the elect are incapable of resisting the Holy Spirit's inward call to repentance and salvation.
P - - Perseverance of the Saints means that all those who are truly saved will certainly be brought to heaven and to glorification and will never be lost.