🔼The name Jaasu in the Bible
The name Jaasu occurs only one time in the Bible. He's a son of Bani and is mentioned among the men who had married and would divorce their foreign wives during the purge of Ezra (Ezra 10:37). In the majority text, this name is spelled as יעשי (Jaasi) but Masoretic scholars changed it to יעשו (Jaasu) for unknown reasons.
🔼Etymology of the name Jaasu
The name Jaasu or Jaasi comes from the verb עשה ('asa), meaning to do, make or accomplish:
The pre-fixed letter yod makes the verb active: he will asa, and the post-fixed yod would generally denote a possessive: asa of [someone]. The final yod may also be seen as a remnant of יה (Yah) = יהו (Yahu) = יו (Yu), which in turn are abbreviated forms of the Tetragrammaton; the name of the Lord: YHWH.
For a meaning of the name Jaasu, NOBSE Study Bible Name List reads Yahweh Makes. Jones' Dictionary of Old Testament Proper Names proposes Made Of The Lord.