INSTANT

[adjective] [not gradable]Something that is instant happens immediately, without any delay.The poison took instant effect.This sort of account offers you instant access to your money.If you want instant gratification, this is one dessert that you can put together in under ten minutes.Contrary to expectations, the film was an instant success.An instant food or drink is one, usually in dried or powder form, that can be prepared very easily and quickly, by adding esp. hot water.instant coffee/soup/mashed potato