Brim/brɪm/ Definition 1 of 3Pro Tip 1/3Container Capacity Use 'brim' to emphasize a container is as full as possible, leaving no space. The jar of cookies was filled to the brim. Pro Tip 2/3Overflowing Implied 'Brim' can imply the possibility of spilling due to being overly full. The boiling pot was bubbling to the brim. Pro Tip 3/3Literal Edge In physical contexts, 'brim' refers to the actual upper boundary of an object. She measured the water up to the cup's brim.