What is the difference between acellular and non-cellular organisms?

Acellular organism - describes any organism or tissue that is a mass of protoplasm which is not divided into cells, such as the plasmodium of some slime molds and the hyphae of some fungi. Not made up of or divided into cells.Also known as unicellular.

Noncellular organism- lacking cellular organization, as applied to viruses, which can only replicate within a cell, whether prokaryotic or eukaryotic.