Tannoy is often used in the UK to refer to a loudspeaker, or a public address system (Tannoy system). It comes from the name of a company that makes sound systems of various sorts, and as such is actually an registered trademark.

Tannoy is a Scottish company formed by Guy R. Fountain in 1926. Guy had invented a solid state rectifier made from a tantalum-lead alloy; he shortened this to Tannoy. Since then Tannoy has done all kinds of sound system related stuff. Aside from its speaker systems, it is known for its dual concentric speakers.