The term 'burden too heavily' can be summarized as 'OVERLOAD' in 8 letters. This phrase is often used to describe a situation where someone is given too much responsibility or work, and is unable to handle it all. It can also refer to a situation where a person is overwhelmed by the amount of stress they are under. In either case, the phrase implies that the person is struggling to cope with the amount of work or stress they are facing.