The meaning of assessment made under this act under section 293 of the Income Tax Act is not defined in the act itself. But we can take guidance from decisions by various high courts. Here are excerpts of courts orders in which the Hon’ble High Court tried to explain the meaning of assessment made under this act.
Meaning of assessment made under this act defined by court
The phrase ‘assessment made under this act‘ used in section 293 of the Income Tax Act came up before Hon’ble Pondicherry High Court in Raleigh Investment Co. Ltd. vs. Governor-General in Council  15 ITR 332 (PC) and it explained.
Meaning : The meaning of the phrase ‘assessment made under this act’ is an assessment finding its origin in an activity of the assessing officer acting as such.
Section 293 of Income Tax Act
Bar of suits in civil courts.
293. No suit shall be brought in any civil court to set aside or modify any proceeding taken or order made under this Act; and no prosecution, suit or other proceeding shall lie against the Government or any officer of the Government for anything in good faith done or intended to be done under this Act.
In this article, you can get guidance from high courts on the meaning of assessment made under this act under section 293 of the Income Tax Act.
Updated up to Finance Act 2021