A funnel in marketing describes the process through which potential customers are guided, from the initial point of contact to the final purchase. The marketing funnel consists of several stages that represent the customer journey.

Funnel marketing focuses on systematically guiding customers through these phases with the goal of prompting a purchase or another desired action at the end. 

An example of a marketing funnel could look like this: A customer becomes aware of a product through an online advertisement (Awareness), researches the product on the website (Interest), compares products (Consideration), and finally makes a purchase (Action).

Thus, the definition of funnel marketing refers to a structured approach where each phase of the funnel is designed to bring the customer closer to making a purchase. This is particularly important in an online or digital marketing funnel, where various digital channels such as email marketing, social media, and landing pages are used to support the process.

To create a marketing funnel means to consciously plan and optimize these phases to increase the conversion rate and to design the sales funnel effectively.