A funnel is a cone-shaped tool, wide at the top and narrow at the bottom, used to pour liquids or small objects into containers with small openings. Without a funnel, trying to pour juice into a narrow water bottle would likely mean spilling half of it on the counter. The funnel catches everything at its wide mouth and guides it smoothly through its narrow spout into the bottle.

The word also describes anything shaped like a funnel. Tornadoes are sometimes called funnel clouds because they taper from wide to narrow as they reach toward the ground. A stadium's crowd might funnel through a single exit gate, with thousands of people squeezing from the open seating area into a narrow passage.

In business, people talk about a sales funnel to describe how many potential customers start at the wide top (maybe seeing an advertisement) but fewer make it through each stage until only some emerge at the narrow bottom as actual buyers. The image works perfectly: a lot goes in at the top, less comes out at the bottom, just like pouring rice through a kitchen funnel.