You can’t delete just one term, when you do the following, it will delete all terms that are setup.

1. Choose Customer Terms from the Setup menu.

2. Click on any term in the list.

3. Hold the CONTROL key (Windows) or the Option key (Macintosh) down and click SAVE.

WARNING: After deleting the list of terms, any existing Customer Invoices or Sales Journal Invoices using the old term will have no term name, but the Days til Due, Early Payment Discount, and Early Payment Due Days will not change unless the invoice is modified and resaved.