For some countries, a switch is enabled at Settings - Document Settings - Estimate name, where you can simply select Quote.
When creating a new document the new document name appears.
- Navigate to Settings – Document settings and choose Custom labels
- Select a language if necessary and change the name from Estimate to Quote or Quotation
- Change also the label Estimate No. to Quote No. or Quotation No.
- Go back and Save the Settings
note: This change happens instantly to all documents