Final answer:
The term referencing an animal's body divided into nearly identical units is segmentation, a key aspect of certain animal body plans allowing for body segment specialization. Segmentation is also associated with bilateral symmetry, which is found in many segmented organisms permitting them to have complex movement and functions.
Step-by-step explanation:
The reference to a type of animal body plan where an animal's body is divided into nearly identical units is describing segmentation. Animals with segmented bodies have their structures divided into repetitive units, which can be seen in organisms such as earthworms and arthropods like insects and crustaceans. This type of body plan allows for specialization of different body segments which can contribute to complex and efficient modes of movement, feeding, and sensory perception.
Segmentation is part of the classification that includes symmetry and developmental pathways. Unlike radial or asymmetrical animals, segmented animals often display bilateral symmetry, meaning they can be divided into mirror-image halves. Other characteristics used to classify animals include the number of tissue layers formed during development, the presence or absence of an internal body cavity, and specific features of embryological development.