A generic trademark, also known as a genericized trademark or proprietary eponym, is a trademark or brand name that, because of its popularity or significance, has become the generic term for, or synonymous with, a general class of products or services, usually against the intentions of the trademark's owner.

Well, a click funnel is basically an online sales funnel, but it’s widely referred to as a click funnel due to the growing popularity of the software called “Clickfunnels”.