ha-lal', hal'-el: In the fifth book of the Psalms (107-50) there are several groups of Hallelujah Psalms: 104 through 106; 111 through 113; 115 through 117; 135; 146 through 150. In the worship of the synagogue Ps 135:1-21 through Ps 136:1-26 and Ps 146:1-10 through Ps 150:1-6 were used in the daily morning service. Ps 113:1-9 through Ps 118:1-29 were called the "Egyp Hallel," and were sung at the feasts of the Passover, Pentecost, Tabernacles and Dedication. At the Passover, Ps 113:1-9 and Ps 114:1-8 (according to the school of Shammai only Ps 113:1-9) were sung before the feast, and Ps 115:1-18 through Ps 118:1-29 after drinking the last cup. The song used by our Lord and the disciples on the night of the betrayal (Mt 26:30), just before the departure for the Mount of Olives, probably included Ps 115:1-18 through Ps 118:1-29.
⇒See the definition of hall in the KJV Dictionary
John Richard Sampey