What is the difference in meaning between these two words: holiday & feast?
British speakers use 'holiday' to mean 'vacation'. For example, 'I went on holiday to Spain last year.' You can also use it in terms like 'a public / national holiday', meaning a day where most businesses are closed.
A feast is a celebratory meal. It's a slightly old-fashioned word, and implies a lot of food for a large number of people.
(Americans use 'holidays' to mean 'public holiday'.)