The term 'ITLL' is an acronym for 'It'll Take A While, ' which is a phrase used to indicate that something will take a significant amount of time. This phrase is often used when someone is asked to do a task that they know will take a while to complete, or when someone is trying to explain why something is taking longer than expected. It can also be used to express the idea that something will take a long time to achieve, such as a goal or a dream.