/ʌlˈtɪriər ˈmoʊtɪv/ – Phrase
Definition: mục đích tiềm ẩn, động cơ ẩn sau
A more thorough explanation: if you have an ulterior motive for doing something then you do it in bad faith for reasons not immediately connected with the action because you think you will get some advantage from doing it
Example: The report said there was an ulterior motive behind the lane closures.