The term 'CULL of DUTY' is a combination of two words, 'CULL' and 'DUTY'. CULL is a verb meaning to select or remove something from a larger group, while DUTY is an obligation or responsibility. Together, the term 'CULL of DUTY' refers to the task of selecting or removing something from a larger group in order to fulfill an obligation or responsibility. This could refer to a variety of tasks, such as sorting through a pile of documents to find the most important ones, or selecting the best candidates for a job.