A funnel usualy referrs to a conversion funnel. A Conversion funnel is the term that describes the steps in a consumer’s journey to becoming a customer. The shape of a funnel represents the gradual decline in the number of customers who reach each step. Not all site visitors continue through to becoming a company’s customer.
Conversion funnel is the primary pathway (or flow) of the user experience where visitors complete a conversion.
The example funnel may look like this: Home page > search results page > product page > checkout.