From Longman Dictionary of Contemporary Englishpizzapiz‧za /ˈpiːtsə/ ●●● S2 noun [countable, uncountable] 
DFFa food made of thin flat round bread, baked with tomato, cheese, and sometimes vegetables or meat on top → pizzeria a slice of pizza
DFFa food made of thin flat round bread, baked with tomato, cheese, and sometimes vegetables or meat on top → pizzeria a slice of pizzaExamples from the Corpus
pizza• Tired from hiking, we checked in, turned on the television and ordered a pizza.• But I like the idea, akin to miniature escargot pizza.• Beer followed pizza and we looked round the Roman amphitheatre which had been built by Roman legionnaires 1,800 years before.• With its pizza boa paint and racing addenda, I thought this car was going to be hellish to drive.• It has a distinctive texture which becomes stringy when cooked and is most famous served on top of pizzas or lasagne.• No self-respecting pasta-maker would use anything else for making fresh pasta or pizza, come to that.• So they decided not to cook on Friday nights and to order pizza for everybody instead.• But when rain comes, they go to pizza.Origin pizza (1800-1900) Italian “pie” 