The word tundish originates from a shallow wooden dish with an outlet channel, fitting into the bunghole of a tun or cask and forming a kind of funnel for filling it.
In contrast to a funnel, the purpose is generally to regulate flow, and achieve a more steady output with intermittent inputs, and the tundish typically will take on a different shape.
The term tundish is still used today in plumbing, where a funnel or hopper is filled by an outlet pipe above it.
This is often provided for intermittent overflows, or where an air gap is required, to avoid possible back-contamination.
It is used to feed molten metal into an ingot mould to avoid splashing and give a smoother flow.