Verb: Cumulate (KYOO-myuh-layt)
1. To gather or pile or become gathered or piled in a heap.
2. a: To combine into one.
b: To increase gradually in quantity or number.
3. To build up by addition of new material.
Sample sentence: I am not sure how it happens, but shoes seem to cumulate in the bottom of my closet to the point where the door won’t close.