https://help.tallysolutions.com/docs/te9rel64/Creating_Masters/Inventory_Info/Altering_a_Units_of_Measure.htm

Altering Units of Measure

You can alter the units of measurement created in Tally.ERP 9.

To alter Units of measurement

1. Go to Gateway of Tally > Inventory Info. > Units of Measure > Alter .

2. Select the Name of Unit you want to alter from the Units list. The Unit Alteration screen appears as shown below:

3. Make the necessary changes.

4. Press Ctrl+A to accept.

You can delete a unit of measure by pressing Alt+D . However, a unit of measure that is part of a compound measure cannot be deleted without deleting the compound measure first.