This origin of this word may be explained as follows...
Worshipping Jesus Christ is vastly more than simply playing/singing songs with His name in them. Worship is a whole-life endeavor of seeking God in everything one does through an honest attempt to obey Him by continually loving Him, loving others, and seeking truth.
Oftentimes Christians refer to going to "worship" when they actually mean to say that they're going to go sing songs with God's name in them. This use of the word "worship" implies that worship is only about music. This is far from the truth; however, worship can involve music. Thus, the word "muship" was formed in the hopes of circumventing the limitation "worship" to a musical setting.
"What time is muship tonight?" "The praise band will start playing at 9:00."