Fissiparous is defined as a plant or animal that breaks apart into smaller parts. It is usually used to describe things that have a tendency to divide or fragment into smaller parts. This can be helpful when it comes to identifying or classifying something. Fissiparous plants have leaves that may be different sizes or shapes. Fissiparous animals have body parts that may be different sizes or shapes. The term can also be used to describe a system or organization that breaks down or disintegrates. This is often due to the fact that parts are separated or lost.