A store admin can delete global and product class attributes on the attribute listing page in the store Admin area:
Global Attributes - Catalog > Classes & Attributes > All Attributes
Product Class Attributes - Catalog > Classes & Attributes > Product Classes
To delete an attribute, use the Trash icon opposite it and confirm the deletion with the Save changes button.
When an attribute is deleted from the listing page, the changes are irreversible and apply storewide. All products that had this attribute assigned will lose the information they contained in this attribute.