Hallelujah is a transliteration of the Hebrew 2pl. imp. הַלְּלוּלָה, literally meaning: praise Jah!
"Jah" is the shorthand for "YHWH" or "Yaweh", and is the revealed name of God in the Old Testament. However, for the Hebrews or Jews the name of YHWH is to holy or sacred to even be uttered; thus, the name in the Old Testament is vocalized and proncounced as "Adonai" אֲדנָי (Lord). Therefore, orthodox jewish singers, such as Josef Karduner, pronounce "Halellu-kah" to avoid desacralizing the name.
The most popular usage context of "Hallelujah" was in contexts of praise, a prime example being the hebrew psalter, where the last five psalms each begin with הללו יה "hallelu Jah". In modern day usage the term has conserved its originally usage context, and is popular in jewish, as in christian liturgy and songs.
הללו יה (Hallelu Jah)
הללו את־יהוה מן־השׁמים הללוהו במרומים (Hallelu et-Adonai min-hashamayim) (halleluhu bameromim)
Praise Jah!
Prais the Lord from the Heavens!
Praise him in the hights! (Ps 148,1)
(In this context the "Hallelujah" is being used to command the congregation to start worshipping the Lord for he is exalted above everything)
Hallelujah is the Greek mode of spelling the Hebrew words, which are translated "Praise Ye Jehovah." Notice Hallelu"jah" ends with Jah. Jah is a shortened form of Jehovah.
Most people have no idea that when they say Hallelujah they are actually saying "Praise Jehovah," the name for the Hebrew, Muslim, Christian God. Hallelujah appears in the Christian Greek scriptures and is a good example that first-century Christians used the divine name.
1. An expression of joy or praise when a slowhalf wit finally cottons on to the painstaking obvious.
2. Expression used to signify having achieved a particular difficult lay.
Hallelujah means to praise God. It is considered the highest praise by some Chistians, and litterally means "Let us praise God".
Hallelujah is also sometimes considered halleluyah, because thats how its pronounced, and because God's names are "Jahova" or short form "Jah", or "Yahwah", or a short form "Yah", which composes the ending of the word.