Focaccia is a flat Italian bread. The baker presses dimples into the dough with their fingers, pours on olive oil, often salt and rosemary, then bakes it. The top comes out golden; the inside stays soft. You tear it, dip it, or split it for a sandwich. It is not pizza: pizza is built as a base for toppings, with tomato as the usual start. Focaccia is the bread itself, even when a bakery puts a little onion or cheese on top.

English borrowed the word as it is, from Italian focaccia. Further back it comes from Late Latin focacium, from Latin focus, “hearth”: this is hearth-bread, the kind baked on the hot stone of the fireplace. French fougasse is a related hearth-bread from that same Latin root.

In English the usual stress is fo-CACH-a (the middle bit like catch, not like cake). Though actually, you will hear a few other stresses from people copying Italian more closely; students will still be understood with fo-CACH-a.