Be blessed by this worship song by Hillsong entitled "Hosanna" with Brooke Frazer as the worship leader.
"Hosanna" (Greek transcription: ὡσαννά, hōsanna) is the cry of praise or adoration shouted in recognition of the Messiahship of Jesus on his entry into Jerusalem, Hosanna! Blessed is the one who comes in the name of the Lord!(Matthew 21:9) It is used in the same way in Christian praise.
Overall, it seems that "Hosanna" is a cry for salvation; while at the same time is a declaration of praise. Therefore, it may be derived that this plea for help is out of an agreeably positive connotation.
The old interpretation "Save, now!" which may be a popular etymology, is based on Psalm 118:25 (Hebrew הוֹשִׁיעָה נָּא hOshEeah-nna) (Possibly "Savior").